9. The Introduction of Christmas as a Federal U.S. Holiday (1870)
On June 28, 1870, President Ulysses S. Grant signed legislation establishing Christmas Day as a federal holiday in the District of Columbia, along with New Year’s Day, Independence Day, and Thanksgiving. This move aimed to standardize holidays across federal jurisdictions and promote national unity following the Civil War. The law initially applied only to federal employees in Washington, D.C., but set a precedent for states to adopt similar measures, leading to broader recognition of Christmas as a public holiday (en.wikipedia.org).
