December saw a major turning point in the war in the Pacific when U.S. and Filipino forces began to get the upper hand against the Japanese in the bloody battles of Guadalcanal, a 2,500 square mile island and a province of the Solomon Islands.
Following the attack on Pearl Harbor a year earlier, Japanese forces advanced into the South Pacific, reaching Guadalcanal in May 1942. In August, U.S. forces chose Guadalcanal for their first major large-scale invasion of a Japanese-held island.
By early December Japanese strength on the island was on the wane due to attrition and shortages of supplies brought on by the build-up of Allied ships, aircraft and troops. On December 31, Emperor Hirohito of Japan gave permission to his troops to withdraw from Guadalcanal, marking the first significant Japanese retreat of the war.
But it would be early February of ’43 before Guadalcanal would be declared secured – after more than six months of ferocious fighting with very heavy casualties on both sides of the conflict