1. The Battle of West Branch: On April 23, 1779, a battle took place in what is now Loyalsock Township, Lycoming County, between a group of British soldiers and Native American allies against a group of colonial soldiers. The battle ended in a stalemate, with both sides suffering casualties.

2. The Pennsylvania Railroad is incorporated: On April 23, 1846, the Pennsylvania state legislature approved the incorporation of the Pennsylvania Railroad. This would become one of the largest and most important railroads in the United States, connecting Pittsburgh to Philadelphia and eventually spreading throughout the country.

3. First World Series game played in Philadelphia: On April 23, 1903, the first ever modern World Series game was played in Philadelphia at Huntington Avenue Grounds (now Huntington Park), between the Pittsburgh Pirates and the Boston Americans (now the Red Sox). The Pirates won the game 7-3.

4. First Earth Day celebrated: On April 23, 1970, the first ever Earth Day was celebrated across the country, with rallies and events promoting environmental consciousness and responsibility. This movement continues to inspire action and awareness to this day.

5. First female governor of Pennsylvania inaugurated: On April 23, 2015, Tom Wolf was inaugurated as the 47th governor of Pennsylvania, alongside the first female lieutenant governor of the Commonwealth, Mike Stack. Wolf was re-elected in 2018 and still holds the position today.