He was involved in violence against civilian targets in pursuit of political aims, today he would be called a “terrorist”, I agree that “terrorist” is a much over-used and often inaccurate term but there are many people who would regard men like Robin Hood today as a “terrorist”, that is a fact.
I dislike the term “terrorist” but in King John’s England a “terrorist” is what Robin Hood would be.
Now, outside of the document, he might have been considered a terrorist, but not in the context of this post.