[1] Apess has been described as "perhaps the most successful activist on behalf of Native American rights in the antebellum United States.

Then five-year-old Apess was cared for by his neighbor, Mr. Furman, for a year until he had recovered from injuries sustained while living with his grandparents.

[6][8] Mrs. Furman, a Baptist, gave William his first memorable experience with Christianity when he was six, and she discussed with him the importance of going to heaven or hell.

He never really wanted to leave, but, despite his reassurances, the family he had come to regard as his own sold his indenture to Judge James Hillhouse, a member of the Connecticut elite.

[citation needed] Apess ran away from General Williams at the age of fifteen and joined a militia in New York, where he fought in the War of 1812.

[citation needed] Troubled by his alcoholism, Apess decided to return home to the Pequot and his family in Massachusetts.

Apess based his narrative on his spiritual conversion, a common genre of the time, and commented also on European-American prejudices against Native Americans.

[11] As was the Methodist practice of the day, Apess became an itinerant preacher; he preached in meetings throughout New England to mixed congregations including Native American, European-American, and African-American audiences.

They wrote to the state government announcing their intention to rule themselves, according to their constitutional rights, and to prevent whites from taking away their wood (a recurring problem).

[14] Lastly, they prevented a settler, William Sampson, from taking wood away from their property and unloaded his wagon.

[15] An attorney assisted them in successfully appealing to the legislature, but initially Governor Levi Lincoln Jr. threatened the group with military force.

[16] The Mashpee protest followed the Nullification Crisis of 1832 on the national level, in which Southern states proposed they could nullify federal law.

The historian Barry O'Connell suggests that Apess intended to highlight the Mashpee attempt to nullify Massachusetts laws discriminating against Native peoples.

[17] Apess continually drew parallels between the desire of free people of color for their rights, particularly Native Americans, and the historic struggle of European-American colonists for independence.

[citation needed] In 1836, he gave a public lecture in the form of a memorial eulogy for King Philip, a seventeenth-century Indian leader who was assassinated by the Plymouth colonists.

At the age of 41, William Apess died of a cerebral hemorrhage (stroke) on April 10, 1839 at 31 Washington Street in New York City.