Ernest was the son of Charles F Montresor, of the Bengal Civil Service. Served in Egypt in 1884 and India in 1888, then later the South African war. He married Sarah Wilhelmina Killick in 1887. He had two daughters, Lena Joan and Millicent Agnes (also listed as Millierat in some records). His wife Sarah died in 1912. Ernest died on Sept 14th1914, as Lieutenant Colonel (commanding officer) of the Royal Sussex Regiment (2nd battalion) in the battle of Aisne. The German troops had surrendered, but an enemy machine gun began firing indiscriminately at soldiers on both sides, killing Ernest and many others in the regiment.