Who wrote the words to the U.S. national anthem, The Star Spangled Banner, during which war?

The famous lyrics were born from a tense, all-night vigil during the British bombardment of Baltimore's Fort McHenry in September 1814. American lawyer and amateur poet Francis Scott Key had boarded a British ship to negotiate a prisoner's release. Detained overnight as the attack began, he could only watch the "bombs bursting in air." When dawn broke and he saw the huge American flag still flying defiantly over the fort, he was so moved that he began to pen the verses of a poem he originally titled "Defence of Fort M'Henry."

His poem was soon set to the tune of a popular and rather boisterous British song, "To Anacreon in Heaven," which was the official song of a London-based gentlemen's music club. The new patriotic song, renamed "The Star-Spangled Banner," quickly gained popularity throughout the 19th century, especially within the military.

Despite its widespread use, it took more than a century for its status to be formalized. It wasn't until 1931 that a congressional act, signed by President Herbert Hoover, officially made "The Star-Spangled Banner" the national anthem of the United States, cementing its place in the nation's history.