According to the Library of Congress, restaurant owner Louis Lassen was the first to serve a beef patty between two slices of bread in 1900. Some food historians claim Fletcher Davis unveiled the burger sandwich at the St. Louis World's Fair in 1904. White Castle co-founder Walter A. Anderson says it was his idea to serve hamburgers on buns.
No matter who invented them, Marc Summers, the host of the Food Network show Unwrapped, says hamburgers beat out the hot dog as America's favorite fast food after World War II.
"When the soldiers came home, they got into their automobiles. Especially in Southern California, there were drive-ins, a la Happy Days, and it became culture right there," Marc says. "White Castle was the number one burger chain."