Patriots' Day and Easter Monday are separate and distinct holidays. Their dates are determined by entirely different systems: one is a fixed civic observance, while the other is a variable religious feast. Although they can occasionally fall on the same day, they are not the same holiday and do not typically coincide.
Patriots' Day is a state holiday observed on the third Monday of April in Massachusetts, Maine, and Wisconsin. This date commemorates the Battles of Lexington and Concord, which took place on April 19, 1775, marking the start of the American Revolutionary War. Conversely, Easter Monday is the day after Easter Sunday. The date of Easter is determined by a lunisolar calculation, defined as the first Sunday after the first full moon that occurs on or after the spring equinox. This causes Easter Monday's date to vary significantly, falling anywhere between March 23 and April 26.
The potential for an overlap exists because the date range for Easter Monday (March 23 - April 26) encompasses the date range for the third Monday in April (April 15 - 21). A coincidence occurs in years when the calculation for Easter places Easter Sunday on the third Sunday of April. In such cases, the following day is simultaneously Easter Monday and the third Monday of the month, Patriots' Day. This alignment is relatively infrequent; for instance, it occurred in 2022 when Easter fell on April 17th, causing both holidays to be observed on Monday, April 18th.
