Francis Scott Key (August 1, 1779 – January 11, 1843) is an American lawyer, author, and amateur poet from Frederick, Maryland who is best known for writing a poem that later becomes the lyrics for the United States' national anthem, "The Star-Spangled Banner".

During the War of 1812, Key observes the British bombardment of Fort McHenry in Maryland in 1814

Key is inspired upon viewing the American flag still flying over the fort at dawn, and writes the poem "Defence of Fort M'Henry", which is published a week later.

The poem is adapted to the tune of the popular song "To Anacreon in Heaven."

The song with Key's lyrics become known as "The Star-Spangled Banner," and slowly gain in popularity as an unofficial anthem over the years, finally achieving official status a century later under President Woodrow Wilson as the United States national anthem.

Key is a lawyer in Maryland and Washington D.C. for four decades, and works on important cases like the Burr conspiracy trial, and argues numerous times before the U.S. Supreme Court.

Nominated for U.S. attorney by President Andrew Jackson, he serves from 1833 to 1841.

Key owns slaves from 1800 but frees them in the 1830s, paying one ex-slave as his farm foreman.

Key publicly criticizes slavery and gives free legal representation to some slaves seeking freedom, but also represents owners of runaway slaves as well.

Key is a devout Episcopalian.

He is also an author of poetry, and often writes on religious themes.

It has been speculated that the U.S. motto "In God We Trust" was adapted from a line in the fourth stanza of the "Star-Spangled Banner".