1. On March 20, 1912, the Alaska Native Brotherhood (ANB) was established in Sitka, Alaska, with a goal of advocating for the rights of Alaska Natives and promoting their culture and traditions.

2. In 1942, on March 20, the Japanese bombed Dutch Harbor, Alaska, in what is known as the Aleutian Islands Campaign of World War II. The bombing marked the only foreign attack on American soil during the war.

3. In 1951, on March 20, the Good Friday earthquake, the largest ever recorded in North America at a magnitude of 9.2, struck the state of Alaska. The earthquake resulted in a deadly tsunami and caused extensive damage throughout the region.

4. On March 20, 1964, the Anchorage International Airport officially opened, replacing Merrill Field as the primary airport in the state. The airport has since become one of the busiest air transportation hubs in the world.

5. In 1989, on March 20, the Exxon Valdez oil spill occurred in Prince William Sound, Alaska, releasing nearly 11 million gallons of crude oil into the ocean. The disaster had devastating impacts on the environment and wildlife in the area, and remains one of the worst oil spills in history.