There's a great book titled "1215: Year of Magna Carta" that addresses your question. Each chapter deals with one or more items in the Magna Carta (the 1215 version), and explains what was going on that inspired that section. It goes over big issues, such as the interactions between King John and King Philip II of France, but it also spends time going over details such as what education opportunities were available to general folks, marriages and other aspects of social life, as well as the training of knights, their equipment, etc.

One interesting section of many in the book goes over "forests": how they were declared, what restrictions were in place, and how people were able to raise revenue from them. This is, of course, a major backdrop of the Robin Hood story.