Originally just a ground beef patty, as it is still interpreted in multiple languages, the first hamburger likely originated in Hamburg (Germany), hence its name; however, evidence also suggests that the United States may have later been the first country where two slices of bread and a ground beef patty were combined into a "hamburger sandwich" and sold as such. Shortly after this combination, the hamburger quickly included all of its currently typically characteristic trimmings, including onions, lettuce, and sliced pickles.
There is still some controversy over the origin of the hamburger – mainly because its two basic ingredients, bread and beef, have been prepared and consumed separately for many years in many countries before their combination. However, after various controversies in the 20th century, including a nutritional controversy in the late 1990s, the burger is now readily identified with the United States, and a particular style of cuisine, namely fast food. Along with fried chicken and apple pie, the hamburger has become a culinary icon in the United States.
The hamburger's international popularity is the result of the larger globalization of food that also includes the rise in global popularity of other national dishes, including the Italian pizza, Chinese fried rice and Japanese sushi. The hamburger has spread from continent to continent, perhaps because it matches familiar elements in different culinary cultures. This global culinary culture has been produced, in part, by the concept of selling processed food, first launched in the 1920s by the White Castle restaurant chain and its founder Edgar Waldo "Billy" Ingram and then refined by McDonald's in the 1940s This global expansion provides economic points of comparison like the Big Mac Index, by which one can compare the purchasing power of different countries where the Big Mac hamburger is sold.
Origins.
Apicius describes a ground meat dish, isicia omentata, which consists of chopped meat wrapped in caul fat and sauteed in a reduction of grape juice. 
Another precursor to the hamburger is steak tartare, a seasoned ground beef patty served raw. It is not known when the first restaurant recipe for steak tartare appeared. While not providing a clear name, the first description of steak tartare was given by Jules Verne in 1875 in his novel "Michael Strogoff". There are certain similarities between steak tartare and the German dishes Labskaus and Mett. 
Other similar raw, chopped meats appeared in the 20th century. One of the oldest references to a Hamburgh ["sic"] Sausage appeared in 1763 in Hannah Glasse's "Art of Cookery, Made Plain and Easy". Hamburgh Sausage is made with minced meat and a variety of spices, including nutmeg, cloves, black pepper, garlic, and salt, and is typically served with toast. Other dishes are also made with minced meat, such as meatloaf, the Serbian pljeskavica, the Arab kofta, and meatballs.
The word "sandwich" was not recorded until the 18th century. Many cultures claim invention of the sandwich, but it was given its name around the year 1765 in honor of the English aristocrat John Montagu, 4th Earl of Sandwich, who preferred to eat sandwiches so he could play cards without soiling his fingers. In 1840 Elizabeth Leslie Cook included a sandwich recipe in her cookbook and it appeared in the local cuisine of the United States.
Hamburg and its port.
Minced meat was a delicacy in medieval cuisine, red meat usually being restricted to the higher classes. Very little mincing was done by medieval butchers or recorded in the cookbooks of the time, perhaps because it was not part of the sausage-making process that preserves meat.
During the first half of the 19th century, most European emigrants to the New World embarked from Hamburg, and New York City was their most common destination. Restaurants in New York offered "Hamburg-style American fillet", or even "beefsteak à la Hambourgeoise". Early American preparations of minced beef were therefore made to fit the tastes of European immigrants, evoking memories of the port of Hamburg and the world they left behind.
Hamburg steak.
In the late 19th century, the Hamburg steak became popular on the menus of many restaurants in the port of New York. This might consist of a fried patty of chopped beef, eggs, onions, and seasoning, or it might be lightly salted and often smoked, and served raw in a dish along with onions and [[bread crumbs]. The oldest document that refers to the Hamburg steak is a [[Delmonico's Restaurant]] menu from 1873 which offered customers an 11-cent plate of Hamburg steak that had been developed by American chef [[Charles Ranhofer]] (1836–1899). This price was high for the time, twice the price of a simple fillet of beef steak. However, by the end of the century the Hamburg steak was gaining popularity because of its ease of preparation decreasing cost. This is evident from its detailed description in some of the most popular cookbooks of the day. Documents show that this preparation style was used by 1887 in some U.S. restaurants and was also used for feeding patients in hospitals; the Hamburg steak was served raw or lightly cooked and was accompanied by a raw [[egg (food)|egg]].
The menus of many American restaurants during the 19th century included a Hamburg beefsteak that was often sold for breakfast. A variant of Hamburg steak is the "[[Salisbury steak]]", which is usually served with a [[gravy]] similar in texture to [[brown sauce]]. Invented by Dr. [[James Salisbury]] (1823–1905), the term "Salisbury steak" has been used in the United States since 1897. Nowadays, in the city of Hamburg as well as in parts of [[northern Germany]], this type dish is called [[Frikadelle]], Frikandelle, or Bulette, which is similar to the meatball. The term "hamburger steak" was replaced by "hamburger" by 1930, which has in turn been somewhat displaced by the simpler term, "burger". The latter term is now commonly used as a suffix to create new words for different variants of the hamburger, including [[cheeseburger]], [[porkburger]], [[bacon]]burger and [[moose]]burger. There are other foods with names derived from German cities that are shortened in different ways in [[American English]]. An example is the [[Hot dog|frankfurter]], often abbreviated as "frank".
Invention.
[[File:DaviesStallStLawrenceMarket.jpg|300px|thumb|left|William Davies Company stall at the St. Lawrence Market in Toronto, Canada. Scenes such as this became common during the early twentieth century in the United States and Canada as the meat market grew rapidly.]]
Many recipes and dishes traveled along with transatlantic immigrants to their destinations in the New World. Some authors question whether the [[Hamburg America Line]] was part of this, arguing that the hamburger was created to meet needs that arose amongst immigrants already in the New World. Others, however, support the thesis that the Hamburg America Line brought the first Hamburger steaks from Europe to the Americas. The hamburger as it is known today has multiple invention claims ranging between 1885 and 1904, but it is well established by the early 20th century. During the following 100 years, the hamburger spread throughout the world as a result of the emerging concept of fast food and a new business model: the [[Chain store|franchise]].
North America.
The industrial use of mechanical meat shredding was the technical advance that helped popularize the Hamburg steak. The first [[meat grinder]] was invented in the early 19th century by the German engineer [[Karl Drais]]. The machine made it possible for minced meat to be sold at market in large quantities at reasonable prices. By 1845, numerous patents existed for improved meat grinders in the United States. These machines could all shred meat to sizes before unimaginable. Before this, minced meat was prepared by hand at home using specialized [[chisel]]s, intensive manual labor that severely limited the amount that could be produced. It is very likely that the invention of the meat grinder contributed directly to the popularization of Hamburg steak, while the steak gradually became distant from its German roots in the minds of many Americans. Minced meat also came to be used in other popular American foods, including [[hot dog]]s and [[meatloaf]].
Another development facilitating the invention and popularization of the proto-hamburger was the increased production of beef through livestock intensification. By the late 19th century, an increasing amount of land was being devoted to cattle and a growing number of people being employed as [[cowboy]]s, resulting in the United States becoming one of the world's largest producers and consumers of beef. The 1880s were declared "The Golden Age of Beef", during which the abundance of rural beef production made vital its transportation by rail from agricultural to urban areas. This gave rise to various methods of meat preservation for making possible the consumption of fresh meat in urban and industrialized areas, among the [[refrigerator car]]s and different methods of packaging meat (such as [[corned beef]]), which were promoted by industrialists like [[Gustavus Swift]] (1839–1903). Around this time, the city of Chicago, along with other cities on the [[East Coast of the United States|East Coast]], became a focal point for the large-scale processing of beef. Beef was already inexpensive at that time, and it was available to the working class. This put the Hamburg steak within reach of the vast majority of the population, giving rise to what some authors jokingly call the "American beef dream". In this era, the number of [[steakhouse]]s that specialized in serving steaks increased markedly; some restaurants even served steak along with seafood, in a dish known as [[Surf and turf]].
The high production and consumption of beef cattle in the United States made the [[meat industry]] increasingly powerful by the end of the 19th century. [[Corporate corruption|Corruption]] problems soon arose in the meat industry, problems that endangered both quality and hygiene. At the beginning of the 20th century, [[Upton Sinclair]] published "[[The Jungle]]", a novel about conspiracies and corruption in the American meat industry, intended as a veiled criticism of the industry itself. The book raised popular awareness about the safety of meat processing and helped lead to the creation of the [[Pure Food and Drug Act]], which was sponsored by the [[Food and Drug Administration]]. "The Jungle" was a milestone in the subsequent history of the hamburger, as it led the American public to force restaurant chains to prove the safety of their cooked meat. In 1933, Arthur Kallett published a similar book, entitled "100 million guinea pigs; Dangers in Everyday foods, drugs, and cosmetics", which warned consumers specifically about the content [[preservative]]s in hamburgers.
Controversial origins.
[[File:Big Mac hamburger - Japan (1).jpg|300px|thumb|The [[Big Mac]] popularized an evolution in the image of the hamburger.]]
Many people have claimed to have invented the hamburger as a sandwich of a ground beef patty placed between two slices of bread. All claims for invention occur between 1885 and 1904, making it probable that the hamburger was created sometime in these two decades. Despite varieties, common elements in these narratives include the claim that the hamburger was born as a food associated with major events such as [[amusement park]]s, [[fair]]s, [[Meeting|conferences]], and festivals. These hypotheses also often share the presence of [[street vendor]]s. 
James A. Cockrell, editor of the "St. Louis Globe-Democrat" states that: "In St. Louis I've heard from person, whose parents or grandparents came from the southern regions of Germany, say that northern Germans in the city of Hamburg were much given to eating ground meat, even in the distant past. Other Germans disapproved of the Hamburg ground meat freaks, especially the Hamburg types who liked raw ground meat. So the St. Louis Germans may have named the sandwich hamburger as a derisive gesture toward the barbaric, ground-meat gobblers in the city of Hamburg. It is certain that the people of Hamburg never got around to making a ground-meat sandwich. If they did it never caught on over there." 
One of the first "birth of the burger" stories belongs to Canton, Ohio, natives Frank and Charles Menches who were food vendors at the 1885 Erie County Fair outside of Buffalo, New York, also known as the Hamburg Fair. According to this story, during the Fair the Menches ran out of their signature menu item of pork sausage sandwiches. Their local supplier, butcher Andrew Klein, was reluctant to butcher more hogs during a period of unseasonable late summer heat and suggested to substitute the use of ground beef. The brothers fired some up, but both found it dry and bland. They added coffee, brown sugar and other ingredients to create a unique taste. The original sandwiches were