1. On April 28, 1789, Maine became a part of the United States. After being a territory of Massachusetts for many years, Maine was finally admitted as the 23rd state of the Union on this day.

2. In 1934, the historic Maine State House in Augusta was destroyed by a fire that broke out on April 27 but continued through April 28. The building, which had served as the state's Capitol since 1832, was completely destroyed.

3. On April 28, 1865, just two weeks after the end of the Civil War, John Wilkes Booth, the assassin of President Abraham Lincoln, was killed by Union soldiers in Virginia. Booth had fled to a farm in Maryland where he was hiding out when he was found and shot.

4. The first Maine International Film Festival was held on April 28, 1998. It was a 7-day event showcasing over 100 films, including a number of world premieres. The festival has since become an annual tradition in the state.

5. On April 28, 2019, the Maine Legislature passed a bill allowing the use of ranked-choice voting in presidential elections. This made Maine the first state in the country to adopt this method for presidential elections, which allows voters to rank candidates in order of preference rather than voting for just one.