1. Maine became the 23rd state of the United States on November 21, 1820. It was the first state to be admitted to the Union under the Missouri Compromise, which aimed to maintain a balance of free and slave states in the country.

2. The Great Fire of Portland, one of the most devastating fires in American history, broke out on November 21, 1866. The fire destroyed more than 1,800 buildings and left around 10,000 people homeless. However, the city was rebuilt within a year of the disaster.

3. On November 21, 1922, the first radio station in Maine, WLBZ, began broadcasting from Bangor. Over the years, the station changed its call letters and ownership several times, and is now known as WVII-TV.

4. On November 21, 1963, Maine Senator Margaret Chase Smith delivered her famous "Declaration of Conscience" speech on the Senate floor. In the speech, Smith criticized her fellow senators for their lack of courage in standing up to Senator Joseph McCarthy's anti-communist witch hunts.

5. The Maine Maritime Academy, a public college in Castine that trains students for careers in the maritime industry, was founded on November 21, 1941. The college offers degrees in marine engineering, marine transportation, and other maritime-related fields.