1. On December 17, 1790, the first U.S. patent was granted to William Pollard of Philadelphia for his invention of a machine for spinning wool. This marked the beginning of a significant period of industrial innovation in Pennsylvania.

2. The Battle of White Marsh, a Revolutionary War engagement between British and American forces, occurred on December 17, 1777, in Montgomery County, Pennsylvania. The battle resulted in a tactical victory for the Americans, who were able to hold off the British and prevent them from advancing southward.

3. December 17, 1819, is the birthdate of Henry Highland Garnet, an abolitionist leader who was born in Kent County, Maryland, but spent much of his life in Pennsylvania. Garnet was an influential figure in the abolitionist movement and was the first African American to deliver a sermon before the U.S. House of Representatives.

4. The groundbreaking ceremony for the Vietnam Veterans Memorial was held on December 17, 1980, in Washington, D.C. The memorial features the names of over 58,000 U.S. military personnel who died during the Vietnam War, including many from Pennsylvania.

5. December 17, 1903, is the birthdate of Raynell Andreychuk, a Canadian politician who was born in Canora, Saskatchewan, which at the time was part of the Northwest Territories. Andreychuk spent a significant part of her career serving as a senator for Saskatchewan and was the first woman to chair the Standing Senate Committee on Foreign Affairs and International Trade.