The escalation in importance of the Wau area had its genesis in the major defeats that befell the Japanese Armed Forces in the South-West Pacific at the end of 1942. As the New Year dawned, the Japanese still held the Papuan beachheads at Buna and Sanananda, but their fate was sealed. Allied air power had prevented any serious reinforcement of those beachheads and the Australian land forces were remorselessly gaining the upper hand. Indeed, the Japanese would try to withdraw as many troops as they could from their lost victories in Papua and at Guadalcanal.

Apart from the imminent loss of the Papuan beachheads and with them the chance to advance overland to Port Moresby, the Japanese had also suffered a major reverse at Guadalcanal in the Solomon Islands. For quite some time the writing had been on the wall, and Admiral Isoruku Yamamoto, the Japanese commander-in-chief, now had to re-evaluate his grand vision of a barrier so far from the shores of Japan. It would subsequently be drawn in closer. The bulwark upon which the Japanese defences in the South-West Pacific would now rest would be the New Guinea mainland north of the Owen Stanley Range and west of the mountainous coastal region around Morobe.

It was a sensible strategy. Any major Allied move would either have to make a long and treacherous passage by sea or, to do what was then considered beyond their means, fly an army across the Owen Stanley Range.