Is it true that there were few restrictions on the power of the English king before 1215?

Before 1215, the English king held considerable power, essentially ruling with very few formal limitations. Think about the Norman Conquest in 1066. William the Conqueror established a strong, centralized monarchy. While there were always advisors and powerful nobles, the king's word was largely law. He controlled land, raised armies, and dispensed justice as he saw fit. This period was characterized by a feudal system where loyalty and service were owed directly to the monarch. It wasn't until King John, facing rebellion from his barons due to heavy taxation and unsuccessful wars, that things began to change. This unrest culminated in the Magna Carta, a document signed in 1215 that, for the first time, placed some restrictions on royal power and protected certain rights of the nobility. So, prior to this landmark agreement, the king's authority was indeed relatively unchecked, making the statement true. It's easy to think that there were always checks and balances, but the concept of limited monarchy was a gradual development.