Walter D. Hubbard was born on October 3, 1840, in Missouri to John Harrison Hubbard and Sarah A. Brooks. By 1860, the family as living in Jackson, Missouri. Hubbard enlisted as a private in Company B of the 6^th Missouri Militia Cavalry on March 1, 1862, and he eventually earned a promotion to 1^st lieutenant. He became a 1^st lieutenant in the 13^th Missouri Cavalry on September 6, 1864, and he was promoted to captain on February 27, 1865. He was promoted to major on March 13, 1865, and finally to lieutenant colonel. He mustered out on June 1, 1866. Hubbard probably married Emily Powell soon afterward, and they had at least two children: Charles, born around 1867; and Walter, born around 1869. The family lived in Springfield, Missouri, after the war, and Hubbard worked as a lawyer. He applied for a federal pension on February 1, 1897, and eventually secured one. He died in Springfield on April 8, 1912.

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