Patriots' Day is a state holiday observed on the third Monday in April in Massachusetts and Maine. It commemorates the anniversary of the Battles of Lexington and Concord, which took place on April 19, 1775, and marked the beginning of the American Revolutionary War. The core of the keyword phrase, "Patriots' Day," functions as a proper noun, a specific name for this observance.
The distinction between the "real" date and the observed holiday is a key point of clarification. The actual historical events that the holiday honors occurred on a fixed date: April 19, 1775. For many years, the holiday was also observed on April 19. However, in 1969, Massachusetts moved the official observance to the third Monday of April to create a three-day weekend, a practice Maine later adopted. Therefore, the "real" historical anniversary is April 19th, while the "real" modern public holiday falls on the third Monday of the month. This holiday should not be confused with Patriot Day, a national day of remembrance held on September 11th to commemorate the 2001 terrorist attacks.
In practice, the modern observance on the third Monday in April is when major commemorative events occur, including historical reenactments and the running of the Boston Marathon. For participants and observers, this Monday is the functional date of Patriots' Day. The term "real" in the query likely stems from the difference between the fixed historical date (April 19th) and the variable date of the official modern holiday (the third Monday in April).
