Modern cultivated lettuce derives from wild lettuce, which originated in Asia Minor, the trans-Caucasus, Iran and Turkestan. According to lettuce expert Edward J. Ryder, the first recorded evidence of lettuce cultivation comes from ancient Egyptian paintings from around 2500 B.C.
According to Aggie Horticulture, the vegetable spread across the ancient world, gracing the tables of Persian kings in the 6th century B.C. and eliciting paeans from Greek writers in the 4th and 5th centuries B.C. The type of lettuce these ancients ate had succulent leaves and an edible stem. The Chinese ate common garden lettuce by the 5th century A.D. Though firm-headed lettuce was known in Europe in the 16th century A.D., historians are not sure where the variety developed.