Born in Perthshire, Scotland, McGregor emigrated with his father's family to the United States in 1856 and settled in Wisconsin.

[1] McGregor farmed and was a teacher and principal of the Waupaca, Wisconsin High School.

McGregor served in the 42nd Wisconsin Volunteer Infantry Regiment during the American Civil War and was commissioned captain.

[1] He also served as the institute conductor and president of the Platteville Normal School.

This article about a Republican Party member of the Wisconsin State Assembly born in the 1830s is a stub.