Duncan Mcarthur, an American pioneer, born in Dutchess co., N. Y., June 14, 1772, died in Ohio, April 28, 1839. His family removed in 1780 to the western frontier of Pennsylvania, and at 18 he left his father's house and participated as a ranger or scout in the warfare with the Indians in Kentucky and Ohio, until the victory of Gen. Wayne in 1797. He soon afterward settled in Ohio as a surveyor, acquired a large landed estate, became a member of the Ohio legislature, and was appointed major general of the territorial militia. In the war of 1812 he received the commission of brigadier general in the army, and after serving for two years as second in command succeeded Gen. Harrison in 1814 in command of the army of the West. In the latter part of this year he partly accomplished a bold plan of conquering Upper Canada, which he was obliged to relinquish from a failure of the forces of Gen. Izard to cooperate with him. After the peace, as a joint commissioner with Gen. Cass, he negotiated the treaty with the Indians of Ohio for the sale of their lands in that state, which was ratified in 1818. He subsequently served again in the Ohio legislature, and in 1823-15 was a representative in congress; and he was governor of the state from 1830 to 1833.