Deep in the archives of the Bodleian Library at the University of Oxford lies a tattered scrap `of paper with newlyweds' scribbles on it. It is a table listing the qualities of a couple. One column reads: "Often says what he does not think," "He does not show his feelings," "He is a Genius"; and the other: "Never says anything she does not think," "She shows her feelings," "She is a Dunce." The writing is Mary Anne Disraeli's, contrasting her own qualities with those of her husband, Benjamin Disraeli, one of the foremost politicians of the Victorian age.

From the outset they made an unlikely couple. Mary Anne was the daughter of a sailor, twelve years Disraeli's senior, and married to someone else when they met. She was also highly eccentric, liable to misbehave, and (worse still) embarrassingly overdressed for grand society dinners. Her Diz was of Jewish descent, a mid-ranking novelist who was mired in debt. They made perfect targets for the vicious Victorian press and society gossips, who pounced on any and every foible. Yet their odd match appeared to make them impervious to such slings and arrows, as together they spun their unusual tale into a romance worthy of the novels they so loved.

Reading between the lines of a great cache of their letters and friends' anecdotes, Daisy Hay shows how the Disraelis rose to the top of the social and political pile. Along the way, we meet women of a similar station and situation whose endings were far unhappier than Mary Anne's, acting as a counterpoint to her fairy-tale status as the landed angel in the prime minister's house.

In an age where first ladies and their husbands are under ever-increasing pressure to perform and to conform,Mr. and Mrs. Disraeli offers a portrait of a political couple who refused to do either.

Daisy Hay is the author of Young Romantics: The Shelleys, Byron, and Other Tangled Lives (FSG, 2010) and has a PhD in English literature from Cambridge University.