Born in Gillingham, Kent, in England, Godley joined the British Army in 1886. He fought in the Boer War and afterwards served in a number of staff positions in England. In 1910 he went to New Zealand as Commandant of the New Zealand Military Forces. Promoted to temporary major general, he reorganised the country's military establishment. Following the outbreak of the First World War, the New Zealand government appointed him as commander of the New Zealand Expeditionary Force, which he led for the duration of the war.