http://en.wikipedia.org/wiki/Sandwich
The first written usage of the English word appeared in
Edward Gibbon's journal, in longhand, referring to "bits of cold meat" as a "Sandwich".
[12] It was named after
John Montagu, 4th Earl of Sandwich, an 18th-century English
aristocrat, although he was neither the inventor nor sustainer of the food. It is said that he ordered his valet to bring him meat tucked between two pieces of bread, and because Montagu also happened to be the Fourth Earl of Sandwich, others began to order
"the same as Sandwich!"[6][7] It is said that Lord Sandwich was fond of this form of food because it allowed him to continue playing cards, particularly
cribbage, while eating without getting his cards greasy from eating meat with his bare hands.
[6]