In 1918, during the fourteenth year of their marriage, Eleanor Roosevelt, age thirty-three, discovered that Franklin, age thirty-six, was in love with her young social secretary, Lucy Mercer. Long afterward, Eleanor told her friend Joseph Lash that the discovery was devastating, that the bottom seemed to have dropped out of her life. Yet as her subsequent history persuasively testifies, it was also her liberating moment, a life-changing event that opened a world of glorious possibilities for a woman not too timid to explore them.
Until then she had been bound to a stifling marriage in which her life was spent in unobtrusively loyal service to Franklin’s gaudy ambition and in childbearing. There had been six pregnancies in the marriage’s first twelve years; sex, she later told her daughter Anna, was an ordeal to be borne.
It was a marriage under constant surveillance by Franklin’s mother, the omnipresent Sara Delano, a live-in mother-in-law out of a Gothic soap opera. Sara cast an...