What event is noted as the first amphibious assault in U.S. history?

The Battle of Nassau, which took place in March 1776, is recognized as the first amphibious assault in U.S. history. This event involved American colonial forces launching a surprise raid on the British-held port of Nassau in the Bahamas. The raid was significant because it marked a novel military strategy for the time, combining naval and land forces to achieve a common objective.

The successful seizure of Nassau provided the Continental Congress with much-needed gunpowder and munitions, which were critical for the cause of independence. This early instance of an amphibious operation demonstrated the effectiveness of coordinating naval and ground troops, a tactic that would become a vital part of U.S. military strategy in future conflicts.

In contrast, the other events listed serve different historical military contexts. The D-Day Invasion occurred during World War II and was a large-scale amphibious assault but came long after the Battle of Nassau. The Siege of Yorktown was a decisive victory in the American Revolutionary War but did not involve the same type of coordinated amphibious attack. Lastly, the Invasion of Grenada was a Cold War-era operation, also involving amphibious assaults, but again not the first instance in U.S. history.