Here are 5 events related to April 1 in Alaska history:

1. On April 1, 1867, the United States government officially took possession of Alaska from Russia. This event is known as the Alaska Purchase, or Treaty of Cession, and it was signed on March 30, but the transfer did not take place until April 1.

2. On April 1, 1915, the Alaska Railroad was incorporated by an act of Congress. The railroad was built to connect coastal ports with interior communities and was completed in 1923. The project was significant for the development of Alaska's economy and transportation infrastructure.

3. On April 1, 1946, a massive earthquake struck the Aleutian Islands, with a magnitude of 8.1 on the Richter scale. The earthquake caused a small tsunami that reached Hawaii and the West Coast of the United States, but no deaths were reported. This was one of the largest earthquakes ever recorded in Alaska.

4. On April 1, 1970, the city of Juneau was designated as the capital of Alaska. Previously, the capital had been located in Sitka and then in Nome, but Juneau was chosen for its central location and accessibility.

5. On April 1, 1985, the Exxon Valdez oil spill occurred in Prince William Sound, Alaska. The spill was caused by the grounding of the tanker, which released over 11 million gallons of crude oil into the ocean. The spill devastated the local ecosystem and had long-lasting effects on the fishing and tourism industries in the area.