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Dedicated in 2011, this monument commemorates Fort McIntosh, the first fort built by American colonists north of the Ohio River during the American Revolution. General Lachlan McIntosh made this fort the headquarters of his small force, but this isolated army also constituted one of the biggest armies west of the Allegheny Mountains. The fort was the site of the signing of the “Treaty of Fort McIntosh” between the representatives of Indian nations from the surrounding area and treaty commissioners. The treaty accelerated western expansion and led to the closure of this fort and the loss of autonomy and land for area Native American tribes.


  • Fort McIntosh Site monument in Beaver County marking the western edge of the fort
  • Traced signatures of the original Treaty of Fort McIntosh, now in the Pennsylvania State Library in Harrisburg
  • Fort McIntosh Site monument in Beaver County marking the western edge of the fort

Built in 1778 above the Ohio River in what is now Beaver, Pennsylvania, Fort McIntosh was commanded by General Lachlan McIntosh. McIntosh is best known today as a duelist who killed one of the signers of the Declaration of Independence, but at this time he had been recently assigned by General George Washington as commander of the Western Department of the Continental Army.

The fort was built to protect the colonist's western frontier from potential Native American attacks and also reduce the likelihood of a British invasion. Not only was it the first Continental Army-constructed fort north of the Ohio River, it was also a direct challenge to Britain and their stronghold of forts in the area of Detroit. The army Lachlan commanded was small in comparison to many others, but Fort McIntosh was home to one of the largest armies west of the Alleghenies, with approximately 1,500 men serving in the area. When the American Revolution ended in 1783, the fort was occupied by only a small number of state militias and supply troops from Fort Pitt and West Point. After the Revolution, the forces here were proclaimed as the First American Regiment by Colonel Josiah Harmar and represented the first permanent peacetime home of the U.S. Army. Although no fighting went on at the location, it is the site of another historic event, the signing of the Treaty of Fort McIntosh.

The treaty inspired Congress in drafting the Land Ordinance of 1785, which set up a system that allowed for settlers to move to the west and purchase land of their own. The treaty was between the United States government and representatives of the Wyandot, Lenape (Delaware), Ojibwa (Chippewa), and Ottawa nations of the surrounding Native American lands. The terms of the treaty and negotiations themselves were not honored in future years. In addition, Native American tribes considered the treaty to be illegitimate as the representatives present were not chiefs and therefore not able to create a binding treaty. In fact, many of the Native Americans were young and did not have authority to negotiate any type of treaty, especially one of this magnitude. Furthermore, colonists may have also used alcohol provided by the American commissioners, Colonel George Rogers Clark and others to influence the representatives of Native Tribes. Some of the most influential military leaders were part of this one-sided treaty, including Richard Butler who led Pennsylvania Continentals at Saratoga, Stony Point, and Yorktown, and Arthur Lee, one of the commissioners who negotiated the French Alliance.

Among other terms of the treaty, Article III stated that Native Americans were to relinquish two-thirds of their land in in southern and eastern Ohio, even though the nations who occupied that space were not present during negotiations at Fort McIntosh. When the Native Americans reminded commissioners that Ohio was meant to forever be their boundary, they replied “we claim this country by right of conquest.” In addition, Native Americans were told France has renounced all claims and Britain, Native American allies, had not stipulated anything in their favor. Because the British had taken sides against the U.S., commissioners claimed the Native Americans needed to come under U.S. protection. Yet, when the treaty was signed, the U.S. failed to follow through on their bargain of preventing new settlement on the small portion of reservation the Native Americans were then left with.

After being de-commissioned in 1788 after 10 years of service, the fort was finally abandoned in 1791, as the frontier was able to push west due to the Treaty of Fort McIntosh. In 1893, Judge Daniel Agnew of Beaver County published Fort McIntosh and Its Times with hope of getting the community interested in the history of the fort and preserving it. In 1974, plans became action when the University of Pittsburgh, Carnegie Museum, and local archaeologists began to excavate and locate the fort’s remains. The excavation lasted four years and over 80,000 identifiable remains and artifacts were located. On the 200th anniversary of Fort McIntosh’s construction, the site was dedicated on October 7, 1978 by U.S. Army General William Westmoreland and the Beaver Heritage Foundation.

Thanks to archaeological studies, many of the locations of barriers of the original fort along with fireplace and wall footers have been marked with bronze plaques. On May 7, 2011, this monument was erected at the western boundary of the fort. Eight other markers within walking distance designate other parts of Fort McIntosh.

  1. “Fort McIntosh Historic Site.” The Beaver Area Heritage Foundation, beaverheritage.org/fort-mcintosh-historic-site/.
  2. “Treaty of Fort McIntosh.” Military Wiki, military.wikia.org/wiki/Treaty_of_Fort_McIntosh.
  3. Treat of Fort McIntosh (1785), Ohio History Connection. Accessed September 12th 2020. https://ohiohistorycentral.org/w/Treaty_of_Fort_McIntosh_(1785).
  4. Fort McIntosh, Borough of Beaver. Accessed September 12th 2020. https://beaverpa.us/history/.
  5. Benington, Dale K.. Fort McIntosh Site 1778-1788, Historical Marker Database. June 16th 2016. Accessed September 12th 2020. https://www.hmdb.org/m.asp?m=44734.
  6. Treaty of Fort McIntosh: 1784 "Forced" Agreement Opened the Ohio Territory for Orderly Settlement, Beaver Area Heritage Foundation. Accessed September 12th 2020. https://beaverheritage.org/treaty-of-fort-mcintosh/.
Image Sources(Click to expand)

Historical Marker Database, Dale K. Benington, July 14, 2011

Beaver Area Heritage Foundation