Guadalcanal is a ten square mile island in the Soloman Island chain, and largely jungle. It was discovered in 1568 by the Spanish but it was part of the British Empire when the Japanese occupied it early in WWII. The U.S. forces chose this as their first major large-scale invasion of a Japanese held island. Guadalcanal was a major turning point in the war. Many ships were sunk (on both sides), but Japan was forced to retreat. It is said that prior to Guadalcanal, the Japanese had always advanced against the US, yet following the battle, they always retreated.
The battle hinged around the airfield which the Americans named Henderson Field, a muddy airstrip hanging onto the edge of the island. It was considered "an unsinkable aircraft carrier". Fighting started on 7th August, 1942 when 11,000 Marines landed at Lunga Point and ended in U.S. victory on 8th February, 1943. There were 24,000 Japanese casualties and 6,000 American.
There were six major naval battles around the island - Savo on 9th August, Eastern Solomons on 24th August, Cape of Hope/Esperance on 11th-12th Sepetember, Santa Cruz Island on 26th and 28th October, Guadalcanal on 12th-13th November and Tassafaronga on 30th November. The Americans lost two aircraft carriers, eight cruisers and fourteen destroyers.