<human>:  When was the Magna Carta signed?
<bot>: The Magna Carta was signed on June 15, 1215. The Magna Carta is an agreement between King John and his barons, in which the king agreed to abide by the laws of the land, and not to impose unjust taxes or to interfere with the rights of the church or the barons. The Magna Carta is considered to be the first document of English law.