I've read seven (I think) histories by Alison Weir. This book is my second novel by her (the first was Innocent Traitor about Lady Jane Grey.) Katherine of Aragon is the first novel in the series, Six Tutor Queens.
Katherine's betrothal to Arthur Prince of Wales was a huge boost to the dynastic hopes of the first Tudor king Henry VII. After Arthur's untimely death, Catherine's future was uncertain: she was a pawn in the ongoing negotiations between King Henry and her father Ferdinand of Aragon. She suffered deprivations and embarrassment of being unable to afford new clothing nor pay her servants.
Her marriage to the new king Henry VIII must have seemed a godsend to her and the fulfillment of her destiny to become Queen of England. In fact, Weir describes an idyllic, fairy tale marriage in the early years.
Miscarriages, stillbirths, and the death of an infant prince brought an end to that.
Despite Henry's abandonment of her and the "dissolution" of their marriage, Katherine remained strong and principled. She never waivered in her belief that she was the true Queen and her daughter Mary was the true heir. She was a remarkable woman.