1) In 1856, a disturbance between Northern and Southern sympathizers in Olympia, WA, erupted into a brawl known as the "Pig War." This conflict, centered around a disputed land boundary between the United States and Canada, was eventually resolved peacefully in 1871 with the signing of the Treaty of Washington.

2) On April 19, 1919, the Seattle General Strike, one of the first and largest general strikes in U.S. history, officially ended. Over 65,000 workers had participated in the strike, which had shut down much of the city's industry for five days.

3) In 1935, the Bonneville Dam, the first dam constructed on the Columbia River, began generating electricity for the first time. The dam was a key part of the New Deal's efforts to create jobs and stimulate economic growth during the Great Depression.

4) On April 19, 1995, the Oklahoma City bombing occurred, killing 168 people and injuring hundreds more. The attack, perpetrated by right-wing extremists Timothy McVeigh and Terry Nichols, remains the deadliest act of domestic terrorism in U.S. history.

5) In 2000, the Seattle Mariners baseball team set a new MLB record by winning their 17th consecutive game to start the season. The Mariners would go on to win a league-leading 91 games that season, but ultimately fell short of a World Series championship.