Early in 1916 the AIF underwent substantial expansion and re-organisation in Egypt. The 1st Division and 4th Infantry Brigade were split in two and their constituent infantry battalions divided, the resulting halves being brought up to strength with recently arrived reinforcements from Australia, forming the 4th and 5th Divisions. The 1st and 2nd Divisions (the latter was retained intact) and the New Zealand Division were formed into I ANZAC Corps under the command of General W.R. Birdwood. II Anzac Corps, comprising the 4th and 5th Australian Divisions was commanded by Lieutenant General Sir Alexander Godley.