I think we all agree that the sandwich is named after the 4th Earl of Sandwich John Montagu (1718-1792). However, why exactly he gave his name to the snack is less certain. It is Edward Gibbon, author of The History of the Decline and Fall of the Roman Empire, who gives us the earliest evidence we have found so far for the word. In a journal entry of 1762 he writes: “I dined at the Cocoa Tree… That respectable body… affords every evening a sight truly English. Twenty or thirty… of the first men in the kingdom… supping at little tables… upon a bit of cold meat, or a Sandwich.”
John Montagu, 4th Earl of Sandwich (1718-1792)
However, it wasn’t until 1770 that we find an account of the word’s origin from a Frenchman, Pierre-Jean Grosley, who was a resident of London in 1765, a few years after Gibbon was writing about sandwiches in his diary. Here is the crucial passage in a 1772 translation:
“A minister of state passed four and twenty hours at a public gaming-table, so absorpt in play, that, during the whole time, he had no subsistence but a bit of beef, between two slices of toasted bread, which he eat without ever quitting the game. This new dish grew highly in vogue, during my residence in London: it was called by the name of the minister, who invented it.”
There are, however, other theories as to why Montagu gave his name to the sandwich. N.A.M. Rodger suggests in his 1993 biography of Montagu that it would have been a convenient snack for the Earl to eat whilst confined to his desk by parliamentary business and a correspondent to the Weekly Entertainer in 1803 tells the following story:
“About thirty-five years ago, the late Lord Sandwich consulted Dr. Glyn, of King's College, Cambridge, for a complaint in his stomach, who advised his lordship to abstain from butter, and to eat in its stead cold meat, unsalted, with his bread, and to eat it often and in small quantities... Lord Sandwich kept open house at his seat near Huntingdon... When chocolate, &c. was handed round as a noonday repast, plates of cold roast meat, between slices of bread, appeared, which his lordship strongly recommended, and called them Sandwiches.”
However, coming back to the question, it is much harder to predict what sandwiches would have been called had John Montagu not come along. There is no shortage of candidates, though, as the English language has produced a number of words for various types of sandwiches, some more specific than others. Here are a few:
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Piece. This is a regional word describing a portion of bread, eaten on its own rather than as part of a meal, or a sandwich. It is first recorded in the 17th century and thus predates the word ‘sandwich’.
Butty. A word from the north of England which originally referred to a slice of bread and butter (hence the name). It is now also used to refer to a sandwich as in ‘bacon butty’ and ‘chip butty’. The Oxford English Dictionary’s earliest evidence so far for the word is from 1855 where it appears in Elizabeth Gaskell’s North and South.
Sarnie. Another British word, arising in the 20th century. However, it would not have arisen independently of the word ‘sandwich’ as it is derived from a colloquial or regional pronunciation of that word’s first syllable. Other regional words based on variations of ‘sandwich’ include ‘sammie’, which is chiefly found in Australia and New Zealand and ‘sanger’, another Australian word.
Dodger. A 20th-century slang term for a piece of bread or a sandwich.
Submarine. A north American term for a sandwich made of a long roll split lengthways and filled with a variety of meats. Also known as a ‘sub’. Our earliest evidence for ‘submarine’ on its own in this sense is from 1949. ‘Submarine sandwich’ is first recorded in 1940.
Hoagie. A U.S. word, of unknown origin, for a submarine sandwich. Our earliest evidence so far is from 1967.