What is the date when the Star Spangled Banner was first published?

Dear Chef Jemichel,

Thank you for using History Hub. According to the Library of Congress, the song was first published September 17, 1814. President Herbert Hoover made it the national anthem in a Public Law of March 1931.

Here are some resources which you may find useful:

Manuscript of the Star Spangled Banner - Maryland Historical Society

"Defense of Fort M'Henry" - Library of Congress