An apple pie is a fruit pie where the main filling is apples. It generally has a top and bottom pastry crust. While the origins of pie are unknown, early versions were made by ancient Egyptians, Romans, and Greeks. Apple pie became popular in America in the 18th century after apples were introduced from Europe. The classic American apple pie descends from 15th century English apple pies but is similar to modern pies with apples, sugar, spices, and bottom and top crusts. Apple pie is often cited as being as American as apple pie but originated elsewhere and was transformed into a distinctly American tradition.