New Georgia Campaign
The Papuan Infantry Battalion advanced along the coast ahead of the 162nd Infantry Regiment and reached Lake Salus on 9 July and then pushed on to Tambu Bay. In mid-July, the advancing US troops came up against strong Japanese defenses positioned a ridge overlooking the bay. This ridge, which provided good observation of Tambu Bay, allowing the Japanese to fire artillery down on to the landing beaches, was later named Roosevelt Ridge by the Americans, naming it after Major Archibald Roosevelt, the commander of the 3rd Battalion of the 162nd Infantry Regiment. The Battle of Roosevelt Ridge was subsequently fought between mid-July and mid-August, concurrently with actions to finally capture the village of Mubo and seize Mount Tambu as the Allies sought to draw reinforcements away from Lae, where an amphibious landing was planned for September 1943. Further afield, the US also launched the New Georgia Campaign.