Pennsylvania Historic Preservation

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Into the Wilderness!: The Search for Thompson’s Island

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Former BHP Keystone interns in front of the Allegheny National Forest headquarters in Warren, PA.

Former BHP Keystone interns in front of the Allegheny National Forest headquarters in Warren, PA.

In July 2014, the Bureau for Historic Preservation received an American Battlefield Protection Program planning grant from the National Park Service to locate, document, and delineate the boundaries of a significant, but little known Revolutionary War conflict site in northwestern Pennsylvania.  The Battle of Thompson’s Island, in present day Warren County, is listed with “Other Sites of Interest” in the 2007 Report to Congress on the Historic Preservation of Revolutionary War and War of 1812 Sites in the United States, but its exact location is unknown.  In fact, it is possible that the battle simply took place near Thompsons Island, not on it—but we are certain that it is located within the Allegheny National Forest.  This project seeks to answer some of those questions. 

War on the Pennsylvania Frontier

As we all know, the American Revolution was a war between soldiers of the British Empire and soldiers, both regular (Continentals) and militia, of the 13 American colonies.  A lesser known aspect of the war was that it included raids on Colonial frontier settlements by British forces, along with Tory forces loyal to the British Crown and their Native American allies, including members of the Iroquois Confederation.  These raids reached a fever pitch in 1778.  Probably the best known of these raids in Pennsylvania was the Battle of Wyoming, also known as the “Wyoming Massacre,” which took place on July 3, 1778.  During the battle, a force of about 400 militiamen took on a force of British Regulars, Tories, and Native Americans.  Of the 400 militiamen who took part in the battle, only 60 would survive; 227 would be scalped by the Native Americans.

Generalized map showing Sullivan’s, Clinton’s, and Brodhead’s campaign against the Iroquois from Trussell, John B., Jr., “The Sullivan and Brodhead Expeditions,” ed. Harold L. Myers.  Historic Pennsylvania Leaflet No. 41.  Harrisburg, PA: Pennsylvania Historical and Museum Commission, 1976.

Generalized map showing Sullivan’s, Clinton’s, and Brodhead’s campaign against the Iroquois from Trussell, John B., Jr., “The Sullivan and Brodhead Expeditions,” ed. Harold L. Myers. Historic Pennsylvania Leaflet No. 41. Harrisburg, PA: Pennsylvania Historical and Museum Commission, 1976.

As a result of raids like the Wyoming Massacre, General George Washington, in 1779, began a campaign against the Native American allies of the British, particularly the Iroquois Confederation.  As part of this campaign, Major General John Sullivan, along with eleven regiments—regimental manpower varied, but a regiment generally included hundreds of soldiers—of Continentals (over 2,300 men total), would march approximately 70 miles northwest from Easton, Pennsylvania, to Wyoming, Pennsylvania.  From there, the troops would march another approximately 70 miles northwest to what was then known as Tioga Point, Pennsylvania; it is now known as Athens, Pennsylvania.  At the same time, Brigadier General James Clinton would lead five regiments of Continentals down the North Branch of the Susquehanna River to meet up with Sullivan.  After the two groups met up they would proceed west to the Finger Lakes of New York, striking at the Iroquois by destroying everything in their path.  They would continue to Genesee, an Iroquois town.

Artist’s rendering of Colonel Daniel Brodhead from Trussell, John B., Jr., “The Sullivan and Brodhead Expeditions,” ed. Harold L. Myers.  Historic Pennsylvania Leaflet No. 41.  Harrisburg, PA: Pennsylvania Historical and Museum Commission, 1976.

Artist’s rendering of Colonel Daniel Brodhead from Trussell, John B., Jr., “The Sullivan and Brodhead Expeditions,” ed. Harold L. Myers. Historic Pennsylvania Leaflet No. 41. Harrisburg, PA: Pennsylvania Historical and Museum Commission, 1976.

As Sullivan was moving north on the eastern side of Pennsylvania, Colonel Daniel Brodhead would lead the 8th Pennsylvania regiment north from Fort Pitt (modern-day Pittsburgh)—Fort Pitt had been decommissioned by the British in 1772 and, during the Revolutionary War, it served as the Western headquarters of the Continental Army— destroying everything in their path.  If feasible, they would meet up with Sullivan in New York and either move on against Fort Niagara or turn back.  On August 11, 1779, Brodhead and his men left from Fort Pitt and headed north, mostly following the Allegheny River.  Around August 18, an advance guard of Brodhead’s men came upon 30 to 40 Allegany Seneca (members of the Iroquois Confederation) and a battle ensued, resulting in 3 American wounded and 5 Seneca killed; the rest retreated.  The battle was the only Revolutionary War battle in northwestern Pennsylvania and is popularly referred to as the Battle of Thompson’s Island.  After the battle, Brodhead continued north, burning Native American villages.  After this, Brodhead’s men returned to Fort Pitt, arriving there on September 14.  The campaign lessened the raids, but they would continue throughout the Revolution.

The Search Begins

With input from stakeholders including the Allegheny National Forest, the Seneca Nation of Indians, and the Friends of the Allegheny Wilderness, we have prepared a Scope of Work to be sent out to several Cultural Resource Management companies for bid.  When the project is completed, we hope to have a detailed history, including GIS mapping, of Brodhead’s campaign from start to finish, a detailed history, including GIS mapping, of the Battle of Thompson’s Island, and archaeological survey to both locate and delineate the boundaries of the battlefield.  We will keep you posted as the project moves forward, so stay tuned!

Author: Keith Heinrich

Keith Heinrich is a Historic Preservation Specialist at the PA SHPO. He handles the National Register program for Western Pennsylvania.

8 Comments

  1. There is a Thompson’s Island Historical Marker already on Route 62 North of Tidioute, PA that shows Thompson’s Island is located in the Allegheny River.

  2. A search of GenealogyBank for “Thompson’s Island” in 1779, didn’t uncover anything. When you repeat the search with “Broadhead”, you’ll find an interesting article which may help you locate the battlefield. (See Wednesday, October 20, 1779 Paper: Pennsylvania Journal (Philadelphia, PA) Issue: 1310 Page: 1.) Brodhead or Broadhead was described as marching from Pittsburg to Mahoning, 15 miles above the Old Kittanning. The soldiers were detained 4 days from rain, then went on a blind, almost impassable path to Cushcushing, described as 15 miles above Venango. There they crossed the Alleghany and marched along the banks where they came upon 30-40 warriors. Lt. Harding started the aggression. It sounds like a brutal and shameful 1-sided attack. Five Native Americans died and the rest were able to get away into the river or into the bushes. They “fled with the utmost horror.” Afterwards the soldiers burned towns and about 600 acres of corn. They crossed on the return about 10 miles above Venango where they burned and plundered more towns.

  3. The battle was on Aug 15 1779
    With a mix of Seneca & Munsee Indians
    The scouts lead by Captain Samuel Brady

  4. I have collected a pretty good number of historical references relating to the area as part of my Allegheny River Islands Wilderness trees report. http://www.nativetreesociety.org/specialreports/ARIW_Report_Dec2011.pdf You can contact me through the Native Tree Society BBS: http://www.ents-bbs.org/

  5. I drive by Thomsons Island quite a bit for work, In fact I think it, ( or a nearby island ) has sign listing it for sale.

  6. Col. Broad head went to a area called Bucktooth where he met heavy resistance. You will find this in the recognized works Emil Russel in 1933 historical record. Proof is in British Records and talking to many old Senecas that heard the story from their hand down family history Much of history of Col. Broadhead campaign is WRONG.

  7. Have you published anything on this search? Thanks

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