In July 1942, a headquarters was raised to command the units that had been sent to Milne Bay, to establish a series of airfields there after the Battle of the Coral Sea. The majority of the staff for this headquarters came from the 1st Division, and at the time of its establishment it was called "C Force" and became Milne Force in August 1942. Only a limited number of troops were assigned, with the first elements being two companies of Militia troops from the 55th Battalion, bolstered later by the arrival of the 7th Infantry Brigade and then the 18th Infantry Brigade, a veteran Second Australian Imperial Force unit. Throughout late August and early September, the Japanese attempted to land troops to capture the airfields and in the Battle of Milne Bay were defeated by the defending Milne Force elements. In October, the 17th Infantry Brigade arrived to relieved the 18th, which was despatched to Buna in December 1942.