There's a little history about our flag that may surprise you, amidst the controversy over NFL football and the National Anthem.

The way we saluted the flag just 75 years ago would shock most of us now.

In fact, much of what we think we know about the flag is wrong.

The troops in the Revolutionary War didn't march under it, and that painting of George Washington carrying it across the Delaware River is fiction.

Nor were soldiers in 1776 singing the Anthem.

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“They were singing Yankee Doodle Dandy,” said historian Marc Leepson, who has written perhaps the most comprehensive biography of the Stars and Stripes.

“The National Anthem did not become the official anthem until 1931,” said Leepson. “The pledge was not recited in Congress until 1988.”

America's near religious devotion to the flag and then Anthem is actually rather new.

American school children only started saluting the flag in 1892, when a minister wrote the Pledge of Allegiance to help heal the wounds of the Civil War.

“They would start out and they would say, 'I pledge allegiance to my flag,’ said Leepson. “And they would hold their right hand up with their palm up toward the person in front of them in a uniting gesture.

It looked an awful lot like a Nazi salute, and in 1942, Americans needed something different. The Flag Code was rewritten to specify that we remove our hats and place our hands over our heart while reciting the pledge.

The Anthem and sports probably dates back to the 1918 World Series between the Chicago Cubs and the Boston Red Sox, when they reportedly played it during the seventh inning stretch.

All through our history, the flag, the pledge and the Anthem have supposed to bring Americans together. It's only now that they seem to be driving us apart.

Leepson writes: “The United States is the only country in the world that has a national Pledge of Allegiance to its flag, a National Anthem that venerates its flag, a national song (John Philip Souza’s “The Stars and Stripes Forever”) that honors its flag, a highly detailed federal law (the U.S. Flag Code) that sets out proper flag procedure, large veterans’ organizations that promote the display of, and dispense advice about, the proper use of the flag (the American Legion and the VFW), and well-organized non-profit nationwide organizations (including the National Flag Foundation, the National Flag Day Foundation, and the Citizens Flag Alliance) that work full-time to promote respect for the flag.”