Hamilton joined the Royal Navy in 1873,[1] and was promoted to commander on 31 December 1895,[2] and to captain on 1 January 1901.

[3] After he retired from the navy, he served as Chief Officer of the London Fire Brigade from 1903 to 1909, and for his service was appointed a Member of the Royal Victorian Order 4th class (MVO) on 19 July 1909.

[4] Hamilton was promoted to rear-admiral on the Retired list on 22 July 1910.

[5] He married Mabel Sang in 1901, and they had a son, William Evelyn de Courcy Hamilton, in late 1902.

[1][6] James de Courcy Hamilton died at his home in London on 24 February 1936, and was cremated at Golders Green.