The Australian Corps was a World War I army corps that contained all five Australian infantry divisions serving on the Western Front. It was the largest corps fielded by the British Empire in France. At its peak the Australian Corps numbered 109,881 men. By 1918 the headquarters consisted of more than 300 personnel of all ranks, including senior staff officers, as well as supporting personnel such as clerks, drivers and batmen. Formed on 1 November 1917, the corps replaced I Anzac Corps while II Anzac Corps, which contained the New Zealand Division, became the British XXII Corps on 31 December. While its structure varied, Australian Corps usually included 4–5 infantry divisions, corps artillery and heavy artillery, a corps flying squadron and captive balloon sections, anti-aircraft batteri