The Pledge of Allegiance of the United States is an expression of allegiance to the flag of the United States and the republic of the United States of America. Such a pledge was first composed, with a text different from the one used at present, by Captain George Thatcher Balch, a Union Army Officer during the Civil War and later a teacher of patriotism in New York City schools. The form of the pledge used today was largely devised by Francis Bellamy in 1892, and formally adopted by Congress as the pledge 50 years later, in 1942. The official name of The Pledge of Allegiance was adopted in 1945. The most recent alteration of its wording came on Flag Day (June 14) in 1954, when the words "under God" were added.