The correct answer to this open question is the following.
Although the question does not provide the video or the link to the video, we can say that the historical context in which Magna Carta was created was the following. The King of England, John I, had exasperated the noble barons of Great Britan. The monarchy in that time had turned to be excessive, arrogant, extremely powerful so people had to put to stop on it. That is when those barons decided to draft Magna Carta to express their unconformity to the monarchy and threaten the king to start a rebellion if he did not sign it. So the agreement that the barons and King John made in Magna Carta was that the king accepted to sign the charter of liberties in which even the monarch was subject to the law. That was one of the provisions that were included in Magna Carta, as well as property rights of the barons, and some freedom for the people.