We Like Robin Hood Costumes But is the Story of a Sherwood Robin Hood True?

We have been seeing Robin Hood movies, reading Robin Hood books and dressing up as Robin Hood for years. Other than the basics we've learned from these sources do we know if the story is true? And if it isn't true, how did the legend get started.

Maxfield Parrish Pablo Picasso Horace Pippin Camille Pissarro Jackson Pollock