The 1884 Washington Nationals were a member of the Union Association. They were managed by Michael Scanlon and finished in seventh place with a record of 47–65. Their home games were played at Capitol Grounds. The Nationals folded with the rest of the Union Association when that league was discontinued after 1884, its only season of operation.
This team should not be confused with the other 1884 Washington Nationals franchise, a different team that played in the American Association the same year.