Observed as a state holiday on the third Monday in April in Massachusetts, Connecticut, North Dakota, and Maine (Patriot’s Day), this holiday commemorates key battles that occurred early in the American War of Independence, particularly the battles of Lexington, Concord and Menotomy. Patriots’ Day is also celebrated in Wisconsin as a public school observance day on April 19 each year.

The Boston Marathon has been run on Patriots' Day since 1897 and the holiday is sometimes referred to as "Marathon Monday.”