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The San Juan Island Boundary Dispute, 1859: Conditions for Peace and Maritime Superiority in a Very Gray Zone

J. Overton

This essay is a selected submission from the 2017 CNO Naval History Essay Contest. The content of the original essay has been copyedited prior to publication.


The 1859 San Juan Island Boundary Dispute, now more commonly called the Pig War, is referenced mostly as a military anomaly and interesting local history footnote. [1] Two great nations nearly went to war in a remote part of the Pacific Northwest over something as minor as a murdered pig, but cooler heads prevailed and everyone lived happily ever after (except, of course, for the aforementioned pig).

The Dispute, however, is a classic example of operations in a Gray Zone, that area described as the “… dominant form of state-to-state rivalry in the coming decades.” [2]  This particular Zone, like some of today, involved conflicts over land which could only be settled by operations at sea. Within this Gray Zone one actor managed to establish and maintained maritime superiority without resorting to violence, and over time, to achieve a favorable end state. The lasting relevance of this event thus deserves further study.

An examination of the Dispute’s operating environment reveals certain conditions that helped facilitate both the weaker power’s maritime superiority and the eventual peaceful resolution to this international crisis. These same conditions can have similar effects in contemporary and future Gray Zones.

“…Between the traditional war and peace duality.”

The Gray Zone concept has recently received considerable attention by military theorists and practitioners. Definitions of this vague operating environment are correspondingly vague. One white paper explains that “Gray Zone challenges are defined as competitive interactions among and within state and non-state actors that fall between the traditional war and peace duality.  They are characterized by ambiguity about the nature of conflict, opacity of the parties involved or uncertainty about the relevant policy and legal frameworks.” [3] A similar description is that these Zones  “…[involve] some aggression or use of force, but in many ways [the] defining characteristic is ambiguity — about the ultimate objectives, the participants, whether international treaties and norms have been violated, and the role that military forces should play in response.” [4]  Among the State actors involved, Gray Zones likely feature a hegemonic or superior power that supports the status quo, and one or more revisionist powers that seek to upset that system. Most importantly, it is suggested that “…large-scale operations in this indistinct landscape will be the dominant form of state-to-state rivalry in the coming decades. Henceforth, international rivalry may be characterized largely by such campaigns….” [5] 

 “The Sovereignty Remains Avowedly in Dispute.”[6]

While the concept and terminology of the Gray Zone is new, the geo-political situation it described is not, and the United States (U.S.) military does have experience operating within them. During the 1840s and 50s, U.S. joint forces operated alongside, and against, many disparate parties in the Puget Sound area of the Pacific Northwest. These operations culminating in direct competition with another Nation state over control of maritime boundaries and islands.

In 1846, the U.S. and Great Britain signed the Treaty of Oregon. It established the 49th parallel “from the Rocky Mountains to the middle of the channel which separates the continent from Vancouver's Island then south through the channel to the Strait of Juan de Fuca and west to the Pacific Ocean” as the boundary between British Columbia and the Oregon Territory, including what would become Washington State. As with many boundary treaties, drafted and signed far from the actual locale in question, ambiguities as to the borderlines remained. The maritime boundary would eventually cause the greatest issue. The “channel” mentioned is actually two separate channels running on either side of the San Juan Islands, so both countries could reasonable claim ownership of the entire Island chain. [7]

The U.S. Army established a permanent presence in the Pacific Northwest in 1848, and built and occupied Fort Steilacoom, near present-day Tacoma, Washington, the next year. They were in place to protect American settlers from incursions of the British, local natives, and the so-called Northern Indians, tribes from British Columbia and Russian Alaska who came to Puget Sound by canoe to trade with, attack, and take prisoners of both natives and settlers. [8]

In 1854, in response to requests from the Washington Territorial government, U.S. Navy and Revenue Marine (a forerunner service of the U.S Coast Guard) ships began making regular patrols in Puget Sound and adjoining Strait of Juan de Fuca to guard against Northern Indian raids. By 1855, all existing branches of the U.S. military, as well as local territorial militia units and interagency partners like the U.S. Lighthouse Service and Coastal Survey, were operating regularly in and around the Puget Sound littoral.[9] The Royal Navy also maintained a presence in and around Vancouver Island, with much the same general mission as U.S. forces, and the Hudson’s Bay Company, a quasi-governmental British corporation, operated its own forts and vessels in the area.

Between1855-56 a confederation of local Indians resisted a series of reservation-forming treaties and fought against local settlers, the U.S. Army and Navy, and local militia. Navy and Revenue Marine officers engaged in several pitched battles that included a naval bombardment to save the tiny village of Seattle, and some land engagements that extended east of the Cascade Mountains before fighting ceased.[10] Simultaneously and independently, Northern Indians threatened mariners and isolated settlements, and fought a battle with U.S. Navy Sailors and Marines near the logging town of Port Gamble. British and American settlers and forces alternated between quarrels, disagreements, and cooperation during these hostilities. Americans fueled tensions when they poured into British Columbia, usually without the government’s permission, seeking fortune after gold strikes. These events challenged British security and sovereignty in the region, and prompted the stationing of more Royal Navy ships in the area, and making British Columbia a British colony in 1858.[11] By then, all the elements of a Gray Zone were evident here: ambiguity about the nature of competition and conflict, “opacity of the parties involved and uncertainty about the relevant policy and legal frameworks,” ambiguity about the role of military forces and the ultimate objectives sought, and rival national powers seeking to either maintain or upend the status quo.[12]

In 1853, the Hudson’s Bay Company had established a sheep farm on the largest of the San Juan Islands, San Juan Island proper. Soon after, American settlers, or “squatters” as the British referred to them, began moving onto San Juan. By spring of 1859, eighteen Americans had made claims on land there also claimed by the Hudson’s Bay Company.[13]

On June 15, 1859, one of these Americans shot a pig owned by the Company, which he found trespassing in what he believed was his rightfully-owned garden. British authorities threatened to arrest him, and consequently, to forcibly evict all American settlers from the Island. The Americans on San Juan brought the matter up with the commander of the U.S. Army’s Department of Oregon, General William Harney, while he visited on a regular patrol of Puget Sound settlements aboard the Army ship Massachusetts. Harney, a veteran of the Mexican War and several Indian wars, responded to their concerns by sending Captain George Pickett and a company of soldiers over on Massachusetts from their fort in nearby Bellingham, Washington. They were based there originally to protect settlers against Northern Indian raids, and would ostensibly to do the same for Americans on San Juan Island. Pickett landed on July 27, 1859, and began building fortifications and attempting to enforce American laws on the disputed island, actions well beyond those needed if the intent was purely Northern Indian defense.[14] When Vancouver Island governor, James Douglas, learned of what his government believed was an invasion of their sovereign territory, he sent British warships to coerce or dislodge Picket’s company, ideally without resorting to force.[15] 

For three tense months, two countries, one the world’s largest empire and greatest naval power and one a rising revisionist nation, faced off and very nearly began their third war against one another. [16] Five conditions facilitated both the weaker party’s effectively gaining maritime superiority, even without their actual Navy vessels in theater, and exploiting that gain to ultimate advantage without firing a shot in anger.

Presence Was More Important Than Capability

In 1859, U.S. land forces in the Puget Sound region consisted of a few small scattered forts equipped and positioned to defend American settlements against Northern Indian raids. Seagoing forces consisted of a few small, scattered vessels of the Revenue Marine, Lighthouse Service, Coast Survey, U.S. Army Quartermaster Corps, and various merchant ships, armed if at all to defend themselves against Northern Indians in canoes. [17] Approximately 2,000 U.S. Army soldiers were in the Pacific Northwest, but the force assigned to San Juan Island had at most 100 troops, two small cannon, and the occasional use of ships Massachusetts, lighthouse tender Shubrick, and mail carrier Julia.

By contrast, British forces, based in the developing installation of Esquimalt on Vancouver Island, had five seagoing warships, totaling 167 guns, all within a few hours sail or steam from San Juan Island. [18] The initial force sent by Douglas to confront Pickett consisted of three of those ships and nearly 1,000 troops, mostly sailors but also 46 Royal Marines and 15 engineers, a useful group for taking and holding ground. [19] The British had the obvious advantage by all traditional measures, yet they were ultimately deterred by the tiny U.S. force. [20] 

Whatever military capabilities were on display, both sides expressed concern that the beginning of an actual kinetic conflict would quickly involve more forces than were arranged on and around the island.  Neither side could decisively attack the other’s Center of Gravity because neither had one in this theater, and both sides knew that a war for this little Island would soon stretch far beyond Puget Sound. Despite the aggressive nature of principals like Harney, Pickett, and Douglas, a quick and decisive victory was unobtainable by either nation-state belligerent.

In this Gray Zone, the very presence of the opposing joint forces, however weak, represented the entirety of the will and means of their respective countries, and hence served as an effective deterrent. As long as maritime operations didn’t involve kinetic violence with the opposing British force, the U.S. forces, even with no actual naval vessels, had at least maritime parity with the Royal Navy.

Mutual Threats Necessitated Cooperation

In the preceding decade, despite numerous confrontations between Americans, British, local natives, and northern Indians, no group collectively regarded any of their adversaries as absolute enemies. The northern Indians were the group most feared by all others, although still not seen as a scourge to be wiped out. [21] Even as the British naval cannons were trained on the small American camp on San Juan Island, relations between the opposing commanders and troops of these two nations were surprisingly cordial. Officers on both sides invited one another to picnics and dinners, and attended church together. [22]

This condition, lacking deep cultural hatreds or vengeance-seeking for past wrongs, and maintained by the isolated and difficult nature of the area, facilitated tolerant coexistence. It also necessitated the two participating nation-state forces cooperating against mutual threats and for mutual gain. Rather than enemies, in this Gray Zone, the parties treated each other as competitors, or what would now be called “actors of concern,” and rather than allies, joined with one another when convenient.

Interagency partners, not always under direct control of their respective countries’ military, could find aligned interests and threats on which to operate. British and American civil magistrates appointed to the island agreed, informally, to work together to enforce laws against crime and vice during the dispute period. [23]

Within this Gray Zone, there were no absolute enemies or permanent allies, and the two most dominant actors had more to fear from outside actors and elements than they did from one another. At times, both countries would need one another exercise some form of effective maritime operation, and again, the fledgling U.S. force had effective maritime parity with its more robust British cousin.

Rational Actors were Influenced by Other Conflicts

Although both U.S. and British Forces in the Northwest had been involved in several “small wars,” lessons of the state-on-state Crimean and Mexican wars were such pervasive factors that they became actual conditions in this operating environment.

British officers were aware of their recent war against near-peer adversaries in the joint warfare of the Crimea, a series of horrific operations for dubious reasons that caused tremendous casualties for unclear goals. Some soldiers, sailors, senior officers, and political actors even had the War of 1812 in mind during this Gray Zone. That war had resulted in much damage and little gain for both belligerents, although the smaller and less experienced U.S. Navy had managed to do more damage than its size and experience probably warranted.[24]

Harney and Picket were veterans of the Mexican War, which yielded far better results for the U.S. than did the Crimean War for Great Britain. But there would be little hope that this time, after the fighting broke out, an American expedition would march on the enemy capital, dictate surrender terms, and increase U.S. territory by one third its previous size.

Other immediate security concerns took precedent even during the tensest days of the dispute. The Northern Indians remained more feared than the British by American military and settlers.[25] A potentially-threatening band of Washington Territory Native Americans caused panic and prompted request for military assistance from the ships supporting Pickett’s encampment, and both Shubrick and Massachusetts were involved in Indian policing duties in other parts of the Sound during the Dispute months.[26]

More than only trying to recreate or avoid past wars, both countries had potential conflicts of more importance impacting their actions. U.S. domestic issues were hinting at some sort of upcoming rebellion or insurrection over State’s rights, which would not be helped by a war with Britain. And British forces on scene were well aware that “… with war taking place between Sardinia, France, and the Austrians…that no one in London would want to start a conflict in the Pacific.” [27]

Operating forces in this Gray Zone shared a general knowledge and appreciation of the causes and costs of other wars. This knowledge lessened the likelihood of repeating those conflict catalysts, and gave the weaker maritime power freer rein, as long as its actions fell short of overt belligerency.

Operational Forces were De Facto Policy Makers

By September 1859, U.S. President James Buchanan learned of the American landing, which had been affected by Harney without political orders, and of the troubles on San Juan Island. He dispatched General Winfield Scott, General of the Army, to the region to negotiate a settlement. Scott, who had both fought and negotiated with the British during his many decades of service, took a six-week voyage from New York to the Northwest. Upon arrival in the Puget Sound area, he began communications with Governor Douglas via messenger. His modest proposal was that the island be jointly occupied, as it had been somewhat already since late July, by small numbers of British and American troops until a lasting political settlement could be reached. On November 9, this proposal, with further details of the Island’s future occupation, legal system, and redress of civilian grievances, was agreed to by Royal Navy Admiral Robert Baynes, Pacific Station Commander for Great Britain, and Douglas.[28] The Pig War, as it was, had ended in an armistice.[29]

Scott, a military leader, was in this Gray Zone acting as a policy maker. But before his arrival, the operational-level joint forces of the United States and Great Britain had played that role. They effectively wielded their respective countries’ diplomatic, informational, economic, and military elements of national power with the mostly-unstated goal of maintaining cessation of hostilities for as long as possible. Wrote one anonymous U.S. soldier while serving on San Juan Island in August, 1859: “As to the cause, necessity, and veritable history of this imbroglio, quien sabe? I must confess that I am too dull to see through it. A few months will solve the mystery. In the meantime we will try and have a good time, and mind strictly our own business.” [30]

Those on scene, with the most to lose should war break out, had already shaped the environment such that conditions were set for reasonable resolution to the dispute once politically-designated policy makers arrived. For varying combinations of the conditions mentioned above, U.S. joint and maritime forces did not need “4.5 acres of diplomacy” inherent in a Nimitz-class nuclear power aircraft carrier to conduct operations at desired times and places and pursue what they saw as the best interest of their nation.

Ambiguity Favored the Revisionist

The San Juan Island Dispute’s catalyst was the pig’s death, and threat of arrest of a citizen on what was believed to be his own nation’s soil by agents of another nation. During these few months, however, forces in theater, their respective governments, and their respective populations had not fixed the value of the object over which they might be fighting. Neither side, at the operational nor strategic level, knew exactly what this Island and maritime boundary was worth.

Ambiguity, the “defining characteristic” of a Gray Zone, served the purpose of omitting a clear military objective or desired end-state by any actor. [31] It also gave an advantage to the revisionist power. Dominant powers, particularly those as globally-engaged as 19th century Great Britain, have a variety of dispersed interests, most far greater than that of a small island with minimal resources or strategic value. The revisionist power, here the younger United States, had far fewer interests, with less to lose, and more to gain proportionately. Typically, the greater power retains the right to draw boundaries, impose culture, and write history. Gray Zone conflicts, however, make the stakes appear insignificant for the greater power and critical for the lesser power. While seemingly being able only to hold its own in this maritime environment, by simply being able to stay on a contested piece of land, whatever its value, and operate to support that force, the weaker power had seized the initiative and gained effective maritime superiority.  

Many Shades of Gray

Scott’s proposal was implemented within months. In 1860, a group of Royal Marines landed on the island’s north end, and an equal-sized detachment of U.S. Soldiers consolidated farther south. Pickett left, then returned to command the U.S. detachment for some months until the outbreak of Civil War and his decision to side with the Confederacy.

Joint occupation lasted until 1872. During those intervening years, ships of the U.S. and Britain resupplied their respective country’s garrisons on the Island and for the most part continued cooperating when their interests aligned. The boundary issue was submitted to third part arbitrators in Europe, who deemed the northwestern Haro Straight channel as the correct maritime boundary, and thus made San Juan Islands were officially recognized as U.S. territory. [32] Much transpired during the years of joint occupation: the U.S. conducted its most destructive war, the northern Indian and native threats in the Puget Sound had been diminished, and the Dominion of Canada had been granted self-governance. The Puget Sound area, while still a wilder corner of North America, was no longer a Gray Zone.

The revisionist actor had retained their effective maritime superiority and “won,” if this victory can be claimed as such, the Pig War. Aspects of the global distribution of power were changed in their favor, and they had achieved this without resorting to actual warfare. [33] But this victory yielded less-than stellar gains. Within months of the Royal Marines leaving the Island, the U.S. military left as well. San Juan Island never supported another large military presence, and was never especially important to sea lanes or border control. Today it is a tourist destination known for its rural beauty, whale watching, and National Park sites at the old British and American camps. The Royal Canadian and U.S. navies both maintain sizable forces in the Puget Sound and Strait of Juan de Fuca areas, and both cooperate regularly in operations ranging from search and rescue to undersea weapons’ testing to oil spill response. The prospect that these two great nations almost went to war here, over a pig or over a maritime boundary, seems absurd.

Modern Gray Zones, and those appearing in the coming decades, may be more complex, with more parties involved, more advanced technology, and greater speed of communication and action.  However, an awareness and understanding, perhaps leading to the development or exploitation, of the above conditions from the San Juan Island Dispute adds some clarity and transparency to the opacity of today’s Gray Zones. That knowledge may help one of the actors achieve, or counter its opponent’s, maritime superiority. It may also serve to tip the scales of war and peace, however slightly, towards peace. 

(This essay was published in the U.S. Naval Institute's Naval History Blog.)


[1] Gordon Robert Lyall. “From Imbroglio to Pig War: The San Juan Island Dispute, 1853-71, in History and Memory.” Journal of B.C. Studies, #186 (2015): 73- 93.

[2]   Michael J. Mazarr.  Mastering the Gray Zone: Understanding a Changing Era of Conflict.  (Carlisle, PA: U.S. Army Strategic Studies Institute, 2015), 2.

[3]  “The Gray Zone” U.S. Special Operations Command White Paper, 1, available at

[4]  David Barno and Nora Bensahel. “Fighting and Winning in the Gray Zone” available at

[5] Mazarr Mastering the Gray Zone, 2.

[6] Vancouver Island Governor James Douglas, as quoted in Michael Vouri, The Pig War: Standoff at Griffin Bay. (Friday Harbor, Washington: Griffin Bay Bookstore, 1999), 42.

[7] For a more in-depth explanation of the treaty, see “The Pig War,” San Juan Island National Park, available at and Vouri, The Pig War, 6- 23. For a map of the 1859 boundaries of this area, see “Know BC,” available at

[8] “For twelve or fifteen years subsequent to the first settlement upon the shores of Puget Sound, among the worst dangers encountered by the whites were the incursions of the Northern Indians.  During these incursions of Northern Indians it fared ill with any force they met or overtook, on land or water, weaker than themselves.”   - Charles Prosch Reminiscences of Washington Territory: Scenes, Incidents and Reflections of the Pioneer Period on Puget Sound. (Seattle, Wa: Ye Galleon Press, 1904) 39.

[9] The most comprehensive history of this conflict, now generally called the Puget Sound War, is J.A. Eckrom, Remembered Drums: A History of the Puget Sound Indian War (Walla Walla, WA: Pioneer Press Books, 1989).

[10] Francis X. Holbrock and John Nikol “The Navy in the Puget Sound War 1855-57.” Pacific Northwest Quarterly, vol. 67, #1 (1976) : 10-20.

[11] Vouri, The Pig War, 24-43, and Barry M. Gough "Turbulent Frontiers and British Expansion: Governor James Douglas, the Royal Navy, and the British Columbia Gold Rushes.” Pacific Historical Review,  Vol. 41  No. 1 (1972):  15-32.

[12] Mazarr Mastering the Gray Zone, 2 and “The Gray Zone” 1.

[13]  “The Pig War,” San Juan Island National Park.

[14] “U.S. Steamer Massachusetts… left Olympia on Saturday last for Bellingham Bay and San Juan Island, under the orders of Lt. Col. Casey, of Fort Steilacoom. It has been determined to take possession of San Juan, and place a garrison upon the island for protection against the Northern Indians. This is a very judicious step, and one that is not taken any too soon; for a lengthy delay in asserting American supremacy there would have rendered our final possession a matter of much greater difficulty than it is now.”  Puget Sound Herald, July 29, 1859, Steilacoom, Washington Territory, 2, accessed at Also Vouri, Pig War, 86.

[15] Vouri, Pig War, 99-114.

[16] “The Pig War,” San Juan Island National Park.

[17] Richard D. White “The Saga of the Side-Wheeled Steamer Shubrick: Pioneer Lighthouse Tender of the Pacific Coast.” The American Neptune, vol. xxxvi, (1976): 45.

[18] Vouri, The Pig War, 99-114.

[19] “The Pig War,” San Juan Island National Park.

[20] For additional analysis of the difficulties of sea control in littoral waters and narrow seas, see Milan Vego “On Littoral Warfare” Naval War College Review, Vol.68, #2 (2015): 30-68.

[21]  Keith A. Murray. The Pig War. (Tacoma, Wa: Washington State Historical Society, 1968): 30.

[22] Vouri, The Pig War, 111. See also “Letters from San Juan,” anonymous letters from American troops on San Juan Island during the Dispute printed the Puget Sound Herald Newspaper on August 19, 1859,  available at

and Puget Sound Herald, October 14, 1859, “…the real fighting men of both nations … [put] forth their best endeavors to avert so great a calamity as a war. It is due alike to the naval officers of Great Britain and the Army officers of the United States that, during the agitation of this subject…they were cultivating social and friendly feelings…” available at

[23] Vouri, The Pig War, 130-153.

[24] British Admiral Baynes had served in the War of 1812 and the Crimean War.

[25] Murray, The Pig War, 27, and Barry M. Gough Gunboat Frontier; British Maritime Authority and Northwest Coast Indians, 1846-1890. (Vancouver, CA, UBC Press, 1984): 109-111.

[26] Puget Sound Herald, Aug 19, 1859, 2, “Doings Below” available at

[27] Murray, The Pig War, 41.

[28] John S. D. Eisenhower Agent of Destiny: The Life and Times of General Winfield Scott. (New York: Free Press, 1997), 338-342.

[29] For more on ongoing Gray Zone examples in this Theater after the Pig War, see Kurt R. Nelson. Fighting for Paradise: A Military History of the Pacific Northwest. (Yardley, Penn: Westholme, 2007),  45-46.

[30] Puget Sound Herald, Aug 19, 1859, 2, available at

[31] More on desired end-states and their impact to conditions and decision making may be found in Joint Publication 5-0, III-11, available at

[32] The Pig War,” San Juan Island National Park.

[33] U.S. actions here, although not holistically planned, were what would now be called “coercive gradualism ” as described by William Pierce, Douglas Douds,  and Michael  Marra “Countering Gray Zone Wars: Understanding Coercive Gradualism” The U.S. Army War College Quarterly Parameters, vol. 45, no. 3 (2015): 51-61, also available at 51

Published: Mon Jan 28 12:24:30 EST 2019