It traditionally consists of meat, which is usually roast beef, ham, or fried seafood such as shrimp, crawfish, fish, oysters, or crab.

Aside from meat and seafood, cheese has also been a recognized ingredient since the Great Depression,[9] the sandwich's inception occurring at the beginning of that period (year 1929).

[13] Roast beef po' boys are commonly offered with "debris" (pronounced ['deɪ bɹi]), which is bits of meat that fall during cooking and are rendered into a near-gravy.

), specifically referring to a type of sandwich, was coined in a New Orleans restaurant owned by Benjamin ("Benny") and Clovis Martin, former streetcar conductors originally from Raceland, Louisiana.

[8] One New Orleans historian finds the Martin claim suspicious for several reasons, starting with the fact that it was not described by the local press until 40 years after the strike, and that prior to 1969 the story from the Martin brothers themselves was that they had created the po' boy for farmers, dock workers and other "poor boys" who frequented their original location near the French Market.

The Martin brothers wrote a letter, reprinted in local newspapers in 1929, promising to feed the streetcar workers, but it referenced "our meal" and made no mention of sandwiches.

The term "po' boy" has spread further and can be found in the South Atlantic States and in California, where it may instead refer to local variations on the submarine sandwich.

[citation needed] Houston has its own variety of the po' boy, with chowchow added to ham, salami and provolone cheese, created in the 1960s and popularized by Syrian and Lebanese restaurateurs.

[24] Vietnamese immigration to the Gulf South, including New Orleans, since the 1970s has led to some crossover between po' boys and bánh mì.