Family can be such a hassle. They’re always asking for money, or a place to stay, or help with getting out of a jam. And when they’re not trying to get stuff out of you, they’re offering unwanted criticism on how you do your job, what you’ve accomplished in life, and giving you suggestions for how you could do it all better. And if you think that being of royal blood gets you off the hook, think again. As Elizabeth I and Mary Queen of Scots learned in their tumultous relationship as royal rivals, it only makes things worse.

In sixteenth-century Europe, the royalty was pretty much all interrelated to varying degrees; generations of intermarrying, inbreeding, and extremely complicated personal relationships made for family trees that were more like dense rainforest undergrowth. So Elizabeth Tudor, queen of England, and Mary Stuart, Queen of Scots, were cousins, and this family tie, as well as the similarities of their situations – solitary reigning queens struggling to hold on to their thrones against religious dissent – made their fight for supremacy all the more complicated and bitter.

As Dunn shows, the two queens came to power under very different circumstances. Elizabeth spent much of her early years in fear for her life, waiting for her elder sister Mary to die so that she could ascend the throne, and defending her claim to succession against Catholic charges of illegitimacy. By contrast, Mary Stuart was queen of Ireland from the moment of her birth, betrothed in infancy to the Dauphin of France, and raised in an atmosphere of luxury, indulgence, and romance. Their backgrounds had an enormous effect on how they ruled as adults: Elizabeth valued intellect, ruling from the head instead of the heart, and felt an enormous burden of duty that eclipsed her personal desires as a woman. Mary, by contrast, was extraordinarily charismatic, relying on her charm and feminine wiles to get her way, but lacked discipline over her wild passions and adventurous nature. Manipulated by her powerful family, Mary came to believe that she was the rightful ruler of England, and never abandoned her claim to the throne. Her refusal to back down, and Elizabeth’s reluctance to undermine her own authority by murdering a fellow queen, formed the backbone of the power struggle that shaped both their lives and the course of history.

Elizabeth’s life is a fascinating one, and difficult to make boring. Nothing new about her story is presented here, but that’s not Dunn’s intention; the novelty is the juxtaposition of Elizabeth’s and Mary’s reigns, comparing the two women and showing both sides of their struggle. Dunn seems to genuinely admire both queens and makes an effort to present them fairly, although her sympathies seem to lie ultimately with Elizabeth. Dunn uses plenty of excerpts from letters between the two women, as well as comments made by the queens about each other, to illustrate their difficult relationship and show its importance in the history of Great Britain. And there are several sections of color plates and pictures to give the reader an image of the major players, and relieve the tedium of text.

Dunn’s writing leaves a bit to be desired. Her major themes – essentially, that Elizabeth ruled with the head and Mary with the heart, and that their similarities as ruling queens bound them together while keeping them apart – are repeated again and again, to the point of being tiresome. For many years, Mary was a royal prisoner whose only recourse was to write Elizabeth begging, accusing, or whining letters pleading for her release, and Dunn falls into repetition here as well, using the same language over and over to develop her themes. The book could have been considerably shortened here without losing the strength of its arguments; the extra padding bogs down the middle section of the book and makes for some tedious reading.

All things considered, Elizabeth and Mary is an interesting, engaging look at the prickly and politically charged relationships among the royal family of the Elizabethan era. To her credit, Dunn is committed to identifying and lauding the differing strengths of Elizabeth and Mary, rather than relying on traditional interpretations or assumptions of their personalities and reigns. Even readers who are familiar with the two queens separately may find much to enjoy in this study of them together.