The Olivieri Brothers Pat and Harry of South Philadelphia have been credited with creating the steak sandwich in the 1930's.  The brothers operated a hot dog stand near South 9th, Wharton St. and Passyunk Avenue in South Philadelphia, site of the current Pat's King of Steaks.

Legend has it that Pat, grew tired of hot dogs and suggested to Harry that he should go to a store and buy some beef. They decided to slice it up, grill it with onions, and piled it onto a roll. A local taxi driver, a regular to the hot dog stand, stopped for a dog but smelled the beef and asked for one of the sandwiches.

After that first sale to the cab driver, word of this savory sandwich spread across the neighborhood and beyond, and the steak sandwich was born.