USS Arizona (BB-39) was a Pennsylvania-class battleship of the United States Navy. The vessel was the first to be named "Arizona". This was done specifically in honor the 48th state's admission into the union, which had happened just the year before the battleship was authorized by Congress. She was commissioned in 1916 and served stateside during World War I. Arizona is best known for her cataclysmic and dramatic sinking, with the loss of 1,177 lives, during the Japanese attack on Pearl Harbor on 7 December 1941, the event that brought about US involvement in World War II. The wreck was not salvaged, and continues to lie at the floor of the harbor. It is the site of a memorial to those who perished on that day.