Complex sentence: Another possible source is an Elizabethan era Welsh soldier of fortune Roger Williams, a national hero in the wars against Spain, would certainly have been known to audiences at the time the play was written and performed.
Split into simpler sentences: Another possible source is an Elizabethan era Welsh soldier of fortune Roger Williams. A national hero in the wars against Spain, he would certainly have been known to audiences at the time the play was written and performed.