on what date did this fight begin?
December 1943.
Introduction
fought between December 1943 and March 1944, 
in which country did the battle of sio take place? Papua New Guinea.
December 1943 December 1943 December 1943
Battle of Sio Battle of Sio Battle of Sio
Introduction Introduction Introduction
The Battle of Sio, fought between December 1943 and March 1944, was the break-out and pursuit phase of General Douglas MacArthur's Huon Peninsula campaign, part of the New Guinea campaign of World War II. The Battle of Sio, fought between December 1943 and March 1944, was the break-out and pursuit phase of General Douglas MacArthur's Huon Peninsula campaign, part of the New Guinea campaign of World War II.  between December 1943 and March 1944, was the break-out and pursuit phase of General Douglas MacArthur's Huon Peninsu
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Battle of Sio [SEP] Introduction
The Battle of Sio, fought between December 1943 and March 1944, was the break-out and pursuit phase of General Douglas MacArthur's Huon Peninsula campaign, part of the New Guinea campaign of World War II. After the defeat of the Japanese in the Battle of Sattelberg, Australian Army forces broke through the Japanese positions around Finschhafen. Constant pressure from US Navy PT boats, Australian land forces and Allied aircraft brought the Japanese logistical system to the brink of collapse, resulting in disease, malnutrition, and privation for the Japanese soldiers. Meanwhile, the Allied supply system grappled with the problems of terrain and climate, particularly inclement weather and rough monsoonal seas that hampered and occasionally prevented delivery of supplies by sea.