The son of state legislator and probate judge Alexander H. Gilmore, he was educated at New London Academy (now Colby-Sawyer College) and began a career as a farmer in Fairlee.

On several occasions he was commended for sustaining the regiment in battle by arranging for the timely acquisition and distribution of food, ammunition and equipment.

[11] In 1882 Gilmore accepted appointment as a colonel on the staff of Governor John L. Barstow, a fellow veteran of the 8th Vermont, and he served until 1883.

He had become ill in March while in town to inspect the local National Guard company, and he remained bedridden in a Bellows Fall hotel while being treated for pneumonia and other ailments.

Their children included Alexander H. Gilmore (June 2, 1866 – February 5, 1939), who became a newspaper editor in Newport News, Virginia, Macon, Georgia, and New Castle, Delaware,[17] and Kathie Gilmore, the wife of Harry B. Chamberlin, a Vermont businessman who served as an officer in Vermont National Guard, joined the army for the Spanish–American War and was later assigned to Alabama, California and other posts throughout the country.