After first appearing in a copy of the Youth's Companion in 1892, as a celebration of the 400th anniversary of the discovery of America, the pledge to the flag received the official recognition of Congress on June 22, 1942. The phrase, "under God," was added to the pledge by Congress on June 14, 1954, by President Dwight D. Eisenhower, who said that "in this way we are reaffirming the transcendence of religious faith in America's heritage and future; in this way we shall constantly strengthen those spiritual weapons which forever will be our country's most powerful resource in peace and war."

When rendering the pledge of allegiance, persons should stand at attention, face the flag, and, if in uniform, salute, or otherwise place the right hand over the heart. Persons wearing the caps of veterans' service organizations, such as the Disabled American Veterans, are expected to salute. Others, such as Boy or Girl Scouts in uniform, should render respect to the flag in accordance with the traditions of the organization whose uniform they are wearing.