Harman Blennerhassett was an Irish-American politician and landowner, born in 1765 in Ireland. He is best known for his involvement in a controversial plot in the early 1800s, which aimed to establish an independent nation in the western territories of the United States. Blennerhassett's estate, located on Blennerhassett Island in the Ohio River, became a focal point for this conspiracy. Blennerhassett was a supporter of Aaron Burr, who was accused of treason for his role in the plot. After the conspiracy unraveled, Blennerhassett faced legal troubles and financial ruin. He eventually moved to England, where he lived until his death in 1831.