A captivating biography of two famous women whose sons, Winston Churchill and Franklin D Roosevelt, would change the course of the 20th century-by award-winning historian Charlotte Gray. Born into upper class America in the same year, 1854, Sara Delano and Jennie Jerome refused to settle into predictable, sheltered lives as little-known wives to prominent men. Instead, both women concentrated their energies on enabling their sons to reach the epicentre of political power on two continents.

In the mid-19th century, the British Empire was at its height, France's Second Empire flourished and the industrial vigour of the USA was catapulting the republic towards the Gilded Age. Sara and Jennie, raised with privilege but subject to the constraints of women's roles at the time, learned how to take control of their destinies, Sara in the prosperous Hudson Valley and Jennie in the glittering world of Imperial London. Yet their personalities and choices were dramatically different.

A vivacious extrovert, Jennie married Lord Randolph Churchill, rising politician and scion of a noble British family. Her deft social and political manoeuvrings helped not only her mercurial husband but, once she was widowed, her ambitious son, Winston. By contrast, deeply conventional Sara Delano married a man as old as her father.

But once widowed, she made Franklin, her only child, the focus of her existence. Thanks in large part to her financial support and to her guidance, Franklin acquired the skills he needed to become a successful politician. Set against one hundred years of history, Passionate Mothers, Powerful Sons is a study in loyalty and resilience.

Gray argues that Jennie and Sara are too often presented as lesser figures rather than two remarkable individuals who were key in shaping the characters of the sons who adored them, and preparing them for leadership on the world stage. A masterful biographer and acclaimed historian, Charlotte Gray breathes new life into Sara and Jennie. Impeccably researched and filled with intriguing social insights, Passionate Mothers, Powerful Sons offers a fascinating and fulsome portrait of how leaders are not just born but made.