In the postwar years, Cornplanter endeavoured to learn more about Euro-American culture and invited Quakers to establish schools in Seneca territory.

He had the schools closed and embraced his half-brother Handsome Lake's movement to return to traditional Seneca ways and religion.

The United States government granted him about 1500 acres of former Seneca territory in Pennsylvania in 1796 for "him and his heirs forever," which became known as the Cornplanter Tract.

When the dam was completed the Cornplanter Tract was flooded and most of the few remaining residents moved to the Allegany Reservation of the federally recognized Seneca Nation of New York.

He was the son of a Seneca woman, Gah-hon-no-neh (She Who Goes to the River), and a Dutch trader, Johannes "John" Abeel II.

[1] The Dutch had settled the Hudson River Valley several generations earlier, and Cornplanter's father, an Albany fur trader, was part of an established family.

The grandfather after whom Cornplanter was named, Johannes Abeel I (1667–1711), was a trader and merchant who built up links with the indigenous people along his trade routes, and who served as the second mayor of Albany.

As the war progressed, however, the British began encouraging the Iroquois to "take up the hatchet," while the Americans sought their continued neutrality.

In July 1777, the Seneca met with John Butler, a deputy superintendent in the British Indian Department at Irondequoit to discuss whether to abandon their neutrality.

Although Cornplanter strongly opposed becoming involved, the Seneca eventually agreed to actively support the British against the Americans.

[5] Cornplanter and Sayenqueraghta were named as war chiefs of the four nations that allied with the British: the Mohawk, Seneca, Onondaga and Cayuga.

During the Siege of Fort Stanwix in August 1777, Cornplanter played a significant role in the ambush of a column of Patriot militia and Oneida at the Battle of Oriskany.

In 1779, George Washington ordered Major General John Sullivan to invade Iroquois territory and destroy their villages.

Cornplanter, along with Joseph Brant, Sayenqueraghta, and Butler, fought a desperate delaying action in order to allow the escape of refugees to Fort Niagara.

[3] A few months later Cornplanter participated in the large scale raid on the Schoharie Creek and Mohawk River valleys that culminated in the inconclusive Battle of Klock's Field.

When the war ended in 1783, Cornplanter recognized the need to develop a positive diplomatic relationship with the fledgling government of what the Iroquois called the "Thirteen Fires."

[1] In 1790, Cornplanter and other Seneca leaders travelled to Philadelphia to meet with President George Washington and Pennsylvania Governor Thomas Mifflin and protest the treatment of their people.

To fight the drunkenness and despair suffered by many Indians, his half-brother Handsome Lake preached that the Seneca must return to the traditional way of life and take part in religious ceremonies.

Upon taking a short ride on the first steamboat to navigate the upper Allegheny River, Cornplanter, while generally impressed with the boat, quipped that "white men will do anything to avoid using their muscles.

He was the uncle of the influential sachem Chainbreaker,[4] and the nephew of Guyasuta, a leader of the western Seneca during Pontiac's War.

James Ross Snowden of Philadelphia gave the dedicatory address, saying in part: He was a dauntless warrior and wisest statesman of his nation, the patriarch of this tribe and the peacemaker of his race.

As we loved him personally, and revere the nobel, manly character he bore, we erect this tribute to his memory, that those who live after us may know and imitate his virtues.

[20][21] "The grounds are located west of the north central Pennsylvania town of Bradford just about 100 yards from the New York state line.