1. On December 4, 1804, the city of Washington formally became the United States' official capital. Prior to this, Philadelphia had served as the temporary capital.

2. The Washington State Capitol Building was completed on December 4, 1928, and has since served as the seat of government for the state of Washington.

3. December 4, 1980, saw the passing of the United States' largest volcanic mudflow in recorded history: the Mount St. Helens Eruption. Over the course of nine hours, a combination of lava, ash, and debris was ejected nearly 15 miles into the atmosphere.

4. The Washington Monument, located in the National Mall in Washington, was dedicated on December 4, 1884. At the time of its completion, it was the tallest structure in the world at over 500ft.

5. On December 4, 1975, Seattle Seahawks were awarded as the 28th franchise of the National Football League (NFL). The team began playing in the NFL in 1976 and plays their home games at Lumen Field (previously known as CenturyLink Field).