The Romans reserved crucifixion for treason, and so Jesus of Nazareth was executed for treason against the Roman state.  The notion he was executed to appease the Jews appears in the last Gospel, chronologically, written in the late 1st or early 2nd century by authors who were not present and did not witness Jesus' life to better appeal to Roman audiences by shifting blame for his death to the Jews (who were despised in the Roman world by that point due to the Revolt a generation after Jesus' ministry).