島国
Grant was the oldest of four siblings. The children's summers, and many of their weekends, were spent at Oatlands, the Long Island country estate built by their grandfather DeForest Manice in the 1830s. As a child, he attended private schools and traveled Europe and the Middle East with his father. He attended Yale University, graduating early and with honors in 1887. He received a law degree from Columbia Law School, and practiced law after graduation; however, his interests were primarily those of a naturalist. He never married and had no children. He first achieved a political reputation when he and his brother, De Forest Grant, took part in the 1894 electoral campaign of New York mayor William Lafayette Strong.