1. Maine Becomes a State - On November 23, 1820, Maine officially became the 23rd state in the United States after having been a part of Massachusetts for over 200 years. Maine joined the Union as a free state, at a time when the issue of slavery was a heated topic across the country.

2. First Thanksgiving Day Proclamation - On November 23, 1817, Maine's Governor William King issued the state's first Thanksgiving Day proclamation, designating the fourth Thursday in November as Thanksgiving Day. This tradition continues to this day, with Maine celebrating Thanksgiving along with the rest of the United States.

3. Birth of a Maine Governor - On November 23, 1963, John R. McKernan Jr. was born in Bangor, Maine. McKernan went on to become the governor of Maine from 1987 to 1995, where he worked on issues such as education and the environment.

4. World War II Naval Tragedy - On November 23, 1944, a U.S. Navy submarine named the USS Corvina was sunk by a Japanese submarine off the coast of Honshu, Japan, killing 82 crew members. The Corvina was the only U.S. submarine lost to enemy action in the Sea of Japan during World War II.

5. Renowned Writer's Visit - On November 23, 1952, renowned American writer Ernest Hemingway visited the small town of Northeast Harbor, Maine, to speak at a local church. Hemingway was known for his literary works such as The Old Man and the Sea and A Farewell to Arms, and his visit to Maine was a notable event for the community.