One dominant theme in Hilary Mantel's Wolf Hall, first novel of a trilogy about the Tudor dynasty, concerns the dangers of rise in power, even the dangers of ambition.
Mantel illustrates the dangers of rising in power and of ambition as she takes the reader through all of the stunts Cromwell performed to remain in good terms with King Henry VIII and ensure the king got what he wanted. Along the way to securing Henry's divorce from Queen Katherine of Aragon, Cromwell separated England from the Roman church; passed legislation forcing all of England's bishops to swear allegiance to the king, not to the pope; had Catholic monasteries closed; and was responsible for the arrests and executions of many priests, as well as of many prominent people, including Thomas More, who was arrested and tried for treason.
Soon, Cromwell has Henry legally established as head of England rather than the pope and Anne Boleyn crowned queen. Yet, the novel leaves the readers wondering if all of the death and destruction Cromwell caused was truly worth the end results. In the end, Anne is unable to produce a male heir, and even her own life is understood to be in jeopardy.
The novel concludes with Cromwell deciding to visit Wolf Hall, family home of Jane Seymour, lady in waiting first to Queen Katherine and then to Queen Anne. Jane Seymour became Henry's third queen, and the title of the book indicates Cromwell sees it is time to distract Henry from Anne through Jane in order to continue to maintain his own favor with Henry and to maintain Henry's power. The ending of the novel also seems to imply that Cromwell's ascension to power has gone as far as it can go; the only place he can go from here is down, and most readers are aware that Cromwell is among the many Henry will soon execute as the trilogy continues.
Hence, all in all, the novel shows that Cromwell's ambitions for rise in power led to nothing but death and destruction, all points that help develop the theme of the dangers of power and excessive ambition.