Alaska as an incorporated U.S. territory

Main articles: Organic act § List of organic acts, and Territory of Alaska
Starting in the 1890s and stretching in some places to the early 1910s, gold rushes in Alaska and the nearby Yukon Territory brought

thousands of miners and settlers to Alaska. Alaska was officially incorporated as an organized territory in 1912. Alaska’s capital, which had been in Sitka until 1906, was moved north to Juneau. Construction of the Alaska Governor’s Mansion began that same year. European immigrants from Norway and Sweden also settled in southeast Alaska, where they entered the fishing and logging industries.

U.S. troops navigate snow and ice during the Battle of Attu in May 1943

During World War II, the Aleutian Islands Campaign focused on Attu, Agattu and Kiska, all which were occupied by the Empire of Japan.[40] During the Japanese occupation, a white American civilian and two United States Navy personnel were killed at Attu and Kiska respectively,

and nearly a total of 50 Aleut civilians and eight sailors were interned in Japan. About half of the Aleuts died during the period of internment.[41] Unalaska/Dutch Harbor and Adak became significant bases for the United States Army, United States Army Air Forces

and United States Navy. The United States Lend-Lease program involved flying American warplanes through Canada to Fairbanks and then Nome; Soviet pilots took possession of these aircraft, ferrying them to fight the German invasion of the Soviet Union. The construction of military bases contributed to the population growth of some Alaskan cities.