It was supposed to be a mundane morning. It was 1909 and Winston Churchill, a British member of parliament, had just arrived in Bristol with his new wife, Clementine. Their task was to greet local party members during a routine political stop.

But suddenly, the low-key event turned deadly. A militant suffragist came out of nowhere and began to attack Winston. He had previously taken a public stance against votes for women, much to his wife’s chagrin. Clementine watched in horror as her husband grappled with the woman. The attacker shoved him toward a moving train—but Clementine pushed through a pile of luggage and literally grabbed him by the coattails, saving his life.

It wasn’t the only time Clementine Churchill would whisk her husband out of danger. During the course of their 57-year-long marriage, Clementine helped her husband get out of political and personal trouble repeatedly. Though she kept a low profile, she was the driving force behind the seemingly bulletproof British prime minister—and Winston himself credited her as the primary driver behind his astonishingly successful life.

Clementine’s life is a success story in and of itself. Born to aristocratic parents, her early life was lonely and marked by rumor and scandal. Clementine’s parents, Lady Blanche Hozier and Henry Montague Hozier, despised one another and were so famously unfaithful that associates assumed none of their children were fathered by Henry. He left Blanche when Clementine was six years old, plunging her mother—a notorious gambler—into relative poverty.

This presented not just financial problems, but social ones. Though it was customary for women of Clementine’s class to become debutantes, Blanche, fearing her bad reputation could harm her daughter, hesitated to launch her into society. Instead, a wealthy aunt did the honors.

In a 2002 interview, Clementine’s daughter Mary blamed that period for her mother’s lifelong anxiety and lack of confidence. The tragic death of Clementine’s 16-year-old sister, Kitty, from typhoid fever, also affected her deeply. Clementine was sent to stay with an aunt during Kitty’s illness, and did not realize she was saying goodbye forever. The incident—and the effects of an unhappy, neglected childhood—stayed with her for the rest of her life.

In 1904, when Clementine was 19, she attended a dance at which 29-year-old Winston Churchill was present. Already a member of parliament, Winston was best known for his noticeable ambition and his dramatic escape from captivity during the Second Boer War. Clementine was not impressed, especially when he did not ask her to dance. “Winston just stared,” she recalled later. “He never uttered one word and was very gauche.”

Four years later, Clementine ran into Winston at a dinner party. This time, she liked him more—and he liked her. After a few months of courtship, they married in 1908.

Like Clementine, Winston had survived a lonely childhood. His parents were cold and distant, leaving him at school for long periods of time and neglecting him; his closest childhood relationship was with his nanny. A spendthrift, Winston was perpetually in debt, but his ambition went further than money. He wanted a career in politics, and he clawed his way into Parliament with a series of dramatic wartime exploits that brought him more and more fame and controversy.

Clementine was ambitious, too—but, cleaving to the social customs of the early 20th century, she poured those instincts into her husband instead of herself. “She once said early in life she would have loved to have been a statesman in her own right if only she had been born with trousers rather than petticoats,” Clementine’s biographer, Sonia Purnell, told NPR.

Clementine never became a statesman, but she helped create one. She steadfastly supported her husband, even when he risked nearly everything to become prime minister. When he insisted on volunteering to fight in the trenches of World War I to redeem himself after championing a disastrous campaign in Gallipoli, she supported him—even warning him not to come back too quickly. She advised him on complex political issues and befriended his allies. And she boosted his confidence during his many bouts with depression, which he called his “black dog.”

Though Clementine had five children with Winston, she spent little time with them. Instead, she threw her efforts behind her husband. However, the tragic fate of her daughter Marigold, who died when she was two years old, deeply traumatized both Winston and Clementine. When her next daughter, Mary, was born a few years later, the couple resolved to raise her differently. She was the only Churchill child who grew up without grappling with alcohol, divorce or suicide: The couple’s oldest daughter, Diana, killed herself with a drug overdose in the 1960s. Randolph struggled with suicide, and Sarah married three times, once without her parent’s knowledge or approval.

The couple spent much of their time apart due to Winston’s demanding schedule, but maintained a lively correspondence. “I tell Clemmie everything,” Winston confided in Franklin Delano Roosevelt.

Clementine was Winston’s rock, but their marriage was anything but peaceful. She loathed his frequent absences and locked horns with him over her more liberal political views. Their arguments became the stuff of family legend, as when Clementine hurled a plate of spinach at him during a spat over money. And sometimes Clementine could not take the stress. She suffered from at least one breakdown and took frequent solo vacations. During one in 1935, she apparently had an affair with an artist named Terence Philip.

The couple had their differences, but when it came to Winston’s career, Clementine was firmly in his corner. Though she never hesitated to give her opinion, as when she told off Charles de Gaulle for suggesting the French would rather turn their guns on the British than help them defeat the Nazis, she also showed up unflinchingly during Churchill’s most trying times.

In 1943, when Winston was nearly prostrated by pneumonia and heart problems, Clementine flew to Carthage to be at his side and nursed him back to health. And again and again, she provided the strength Winston needed to bounce back and lead a country in crisis.

During the darkest days of World War II, the world needed heroes. It found one in Winston Churchill, the statesman whose speeches helped keep Britain and its allies going in times of hardship, deprivation and death.

“We shall fight on the beaches,” he told a radio audience in 1940. “We shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender.”

The words were about Britain’s evacuation of Dunkirk but they could just as easily have been about Clementine, the woman who helped her husband conquer two world wars—and his personal demons.