There have been many claims about the origin of the hamburger, but the origins remain unclear. The popular book "The Art of Cookery made Plain and Easy" by Hannah Glasse included a recipe in 1758 as "Hamburgh sausage", which suggested to serve it "roasted with toasted bread under it". A similar snack was also popular in Hamburg by the name "Rundstück warm" ("bread roll warm") in 1869 or earlier, and supposedly eaten by many emigrants on their way to America, but may have contained roasted beefsteak rather than Frikadeller. Hamburg steak is reported to have been served between two pieces of bread on the Hamburg America Line, which began operations in 1847. Each of these may mark the invention of the Hamburger, and explain the name.
There is a reference to a "Hamburg steak" as early as 1884 in the Boston Journal.[OED, under "steak"] On July 5, 1896, the Chicago Daily Tribune made a highly specific claim regarding a "hamburger sandwich" in an article about a "Sandwich Car": "A distinguished favorite, only five cents, is Hamburger steak sandwich, the meat for which is kept ready in small patties and 'cooked while you wait' on the gasoline range."
Claims of invention
According to Congresswoman Rosa DeLauro, the hamburger, a ground meat patty between two slices of bread, was first created in America in 1900 by Louis Lassen, a Danish immigrant, owner of Louis' Lunch in New Haven, Connecticut. There have been rival claims by Charlie Nagreen, Frank and Charles Menches, Oscar Weber Bilby, and Fletcher Davis. White Castle traces the origin of the hamburger to Hamburg, Germany with its invention by Otto Kuase. However, it gained national recognition at the 1904 St. Louis World's Fair when the New York Tribune referred to the hamburger as "the innovation of a food vendor on the pike". No conclusive argument has ever ended the dispute over invention. An article from ABC News sums up: "One problem is that there is little written history. Another issue is that the spread of the burger happened largely at the World's Fair, from tiny vendors that came and went in an instant. And it is entirely possible that more than one person came up with the idea at the same time in different parts of the country."