[2][a] Walker's parents separated when he was young, and his mother married Donald Grant of Chenango, New York.

[2] In 1854, Walker received a Bachelor of Arts degree from Hamilton College in Clinton, New York.

[2] His other business ventures included serving on the board of directors of the American Fire Insurance Company of Norfolk.

[9] Walker was also a director of the Atlantic Iron Works and Dock Company and served as its president from 1866 to 1869.

[2] Walker remained active in business ventures, including serving as president of the New York Underground Railroad Company.