Who invented the burger?

There are several claims to how the first burger or hamburger came to be. It was first created in the US around 1890, but became popular at the 1904 St. Louis World's Fair when the New York Tribune namelessly attributed the hamburger as, "the innovation of a food vendor on the pike."

White Castle says the hamburger originated in Hamburg, Germany with its invention by Otto Kuase when he created a beef patty cooked in butter, topped with a fried egg. .

Others who claim to have invented the hamburger are:

Charlie Nagreen was fifteen when he reportedly made sandwiches out of meatballs that he was selling at the 1885 Seymour Fair (now the Outagamie County Fair), so that customers could eat while walking.

Frank and Charles Menches who ran out of pork sausage for their sandwiches and substituted chopped beef.

Oscar Weber Bilby served hamburger on a bun at a 4th of July celebration.

Louis Lasson ran out of steak at his lunch wagon so he used some beef trimmings to make a sandwich for a customer.

Fletcher David served a 'burger' of fried ground beef patties with mustard and Bermuda onion between two slices of bread; with a pickle on the side at his lunch stand.