The Battle of Attu Took Place on American Soil
However, not all of World War II was fought on European soil. The only conflict to occur on American soil was the Battle of Attu. Attu Island, which is a portion of Alaska's Aleutian Islands in the North Pacific, saw combat between Japanese and American forces in May 1943. Attu Island had a population of just 40 people.
The islands had been assaulted by the Japanese in June 1942, but US forces didn't retake them until 1943. 12,500 US soldiers were deployed to the island on May 11 and engaged Japanese forces for two full weeks.
The combat was intense, and the terrain was harsh, despite how small the island was. Not the Japanese, but illnesses and non-combat casualties including frostbite, trench foot, fevers, and even famine claimed the lives of over 2,100 US soldiers. The situation became so critical that some soldiers began tossing grenades into the water to kill fish for sustenance.
When the Americans ultimately took control, more than 2,350 Japanese soldiers were dead, many of them by their own hands after using grenades to commit suicide. Over 1,700 Japanese soldiers had been killed by enemy troops.