Yes, legend has it that the Earl of Sandwich came up with the idea of putting meat between two pieces of bread. maybe true. No way to know for sure. But, kind of hard to believe that no one in the entire history of bread making never, ever made/eaten meat on bread. In any event, 260 plus years have passed, and people, the world over, greatly expanded on the idea.
Finally, their are numerous countries that rarely make sliced bread. They make large and small rolls. It is then a simple matter of slicing those rolls and filling them with various ingredients.
Back in the days before slicing machines were invented, men needed portable food to take to work at a factory. Men in New Orleans , on their way to work, stopped off at the local bakery and asked them to make sandwiches. The idea of Po’ Boys was born. A Po’ Boy is a sandwich, made with a sliced roll and filled with meat and salad. Their are dozens of different fillings for Po’ Boys. Hot ones are usually meant to be eaten immediately, while cold one are often carried to work.
Bruce, if you can show me that the Earl of Sandwich claimed that a sandwich is ONLY made with sliced bread and NEVER, EVER made with a roll, then you contention might have some merit. In the meantime, the vast majority of the world will continue to call any two pieces of bread and filled, and picked up with the hands and eaten, is indeed a sandwich.