Alaska

August 20, 1741 – Alaska was discovered by Danish navigator Vitus Jonas Bering, hence the name of the Bering Strait. It did not become a state in the United States until 1959.

https://www.alaskacenters.gov/explore/culture/history#:~:text=In%201741%2C%20A%20Russian%20expedition,is%20now%20the%20Cook%20Inlet