Which U.S. Navy installation housed the Pacific Fleet headquarters before the Pearl Harbor attack?

Naval Station Pearl Harbor housed the U.S. Pacific Fleet headquarters before the attack.

Pearl Harbor was a major naval base on Oahu and the home port of the U.S. Pacific Fleet. Its protected harbor, repair facilities, fuel infrastructure, and strategic position made it more useful for Pacific operations than the fleet’s earlier base on the U.S. West Coast. The move increased American reach but also placed many important ships and personnel within range of a surprise Japanese attack.

The installation should not be confused with nearby Ford Island, a naval air station located inside the harbor, or Hickam Field, an Army air base beside it. In 1941 these locations formed a connected military complex but remained distinct commands and facilities. Today, the harbor area is part of Joint Base Pearl Harbor–Hickam and remains an active U.S. military installation.