The cause of the U.S. participation was pirates from the Barbary States seizing American merchant ships and holding the crews for ransom, demanding the U.S. pay tribute to the Barbary rulers. United States President Thomas Jefferson refused to pay this tribute. Sweden had been at war with the Tripolitans since 1800. So the Barbary pirates.
The answer is technically false. All of these years are within the fifteenth century, except for 1401. The fifteenth century a.d. lasted from 1401 - 1500.
