1. On October 31, 1954, President Dwight D. Eisenhower officially designated the Puget Sound Naval Shipyard in Bremerton as the official overhaul and repair facility for the nuclear-powered submarine fleet of the United States Navy. This designation marked the start of Puget Sound's long history of servicing and repairing the Navy's submarines.

2. On October 31, 1975, the Washington State Capitol in Olympia was officially dedicated by Governor Dan Evans and other state officials. The building, which had been under construction since 1911, had undergone extensive renovations over the years and the dedication ceremony marked the completion of the last major phase of the project.

3. On October 31, 1979, Seattle Mariners baseball player Willie Horton became the team's first-ever free agent signee when he agreed to a two-year contract worth $1.8 million. Horton, who had previously played for the Detroit Tigers and Texas Rangers, would go on to play two seasons for the Mariners before retiring in 1980.

4. On October 31, 1980, the World Series championship parade for the Seattle SuperSonics basketball team was held in downtown Seattle. The Sonics had won their first-ever NBA championship the previous season, defeating the Washington Bullets in five games. The parade drew tens of thousands of fans and culminated in a rally at the Seattle Center.

5. On October 31, 1999, the Washington State Ferries system set a new record for daily ridership when over 109,000 passengers used the system on Halloween. The record-breaking day was attributed to a combination of Halloween revelers and football fans traveling to and from the University of Washington's homecoming game.