Francis Bellamy, the author of these words, was an ordained minister, magazine writer, and Freemason who stated that his aim was to say "what our republic meant and what was the underlying spirit of its life." Bellamy wrote the Pledge of Allegiance in 1892 as part of the national celebration of the 400th anniversary of the discovery of America by Columbus. It was embraced by the nation and immediately became part of the school-day ritual. Bellamy’s original text (below) has been altered twice. In 1923, the words "the flag of the United States of America" were substituted for the words "my flag." Congress officially recognized the Pledge in 1942 and added the words "under God" in 1954.
Source: The National Flag Day Foundation, Inc. 418 South Broadway, Baltimore, Maryland 21231