Though Jack Straw is mentioned in the historical record along with a brief confession, we know nothing else about this English rebel. So his life story as told in this novel is the invention of the author. Zelitch's choice to make her protagonist an easily influenced follower type is one of the reasons why I became steadily less impressed with this novel as I went on.
I thought that the most sympathetic character was John Ball, a pivotal figure in the Peasants' Revolt. The article that I've linked is a thorough and enlightening profile by leftist historian John Simkin. Ball's radical preaching inspired many who might otherwise have been inclined to merely grumble about the terrible injustices that were taking place during this period. I learned from this novel that John Ball was actually the author of the famous quote "When Adam delved and Eve span who was then the gentleman?" Zelitch portrays John Ball as a mentor and father figure to the central character. I was bothered by his having been dishonored and degraded later in the novel by people who owed him a great deal.
My own readings in history have shown me that every well intentioned revolution or revolt has been corrupted or co-opted for far less high-minded purposes. It neither surprised nor disappointed me that the same thing happened to the Peasants' Revolt, but reading about it was a depressing experience.
I did like Jack Straw's role as a storyteller. A couple of the stories he told were enjoyable, and I considered them high points in The Confession of Jack Straw.