In aproximately what years did last names become hereditary for most English pea

Question:

In aproximately what years did last names become hereditary for most English peasants?

I know many experts tell us that surnames have been around since the Norman Conquest in 1066, but they didn't become hereditary until anywhere from the 1200s to the 1400s, depending on class and where on lived in England. That's a wide range of years, so I was curious if any of you could narrow that down considerably. For instance, when did the common peasant in middle England start passing his last name down to his children?

Best Answer - Chosen by Asker: I'm not too sure about the peasant class since my ancestory has been through William Marshall.. but it seems right around 1200s where I first started seeing someone going after a last name. Ex. William Marshall since his father was Grand Marshall of such-n-such. Also FitzRoy started to show up, which means a bastard of a royal, thought to give you some trivia.