Born in Roseneath, Wellington, New Zealand, Wake's family moved to Sydney, Australia in 1914. She was two years old at the time, and the youngest and most independent of six children. Later, her father left the family to return to New Zealand, leaving her mother to raise the children.

In Sydney, she attended the North Sydney Girls High School. At the age of 16, she ran away from home and worked as a nurse. With £200 that she had received from the will of an aunt, she journeyed to New York, then London where she trained herself as a journalist. In the 1930s she worked in Paris. Later she worked for Hearst newspapers' European correspondent. In 1939 she witnessed the rise of Adolf Hitler, Nazis, and saw the violence towards Jews, gypsies, blacks and protesters on the Paris streets and in Vienna.

Later, in 1939 she met wealthy French industrialist Henri Edmond Fiocca, whom she married on 30 November. She was living in Marseille, France when Germany invaded. After the fall of France, she became a courier for the French Resistance and later joined the escape network of Captain Ian Garrow. The Gestapo - Secret State Police was the official secret police of Nazi Germany called her the "White Mouse". The Resistance had to be very careful with her missions as her life was in constant danger and the Gestapo were tapping her phone and intercepting her mail.[citation needed]

By 1943, she was the Gestapo's most-wanted person, with a 5 million-franc price on her head. When the network was betrayed in December 1943, she had to flee Marseille. Her husband Henri stayed behind where later, unknown to Nancy, he was captured, tortured and executed by the Germans. Wake had been arrested in Toulouse, but was released four days later. Her sixth attempt to cross the Pyrenees to Spain succeeded. She went to Britain and joined the Special Operations Executive. On the night of 29–30 April 1944, Wake parachuted into the Auvergne and became a liaison between London and the local maquis group headed by Captain Henri Tardivat. She coordinated resistance activity prior to the Normandy Invasion and recruited more members. She also led attacks on German installations and the local Gestapo HQ in Montluçon.[citation needed]

From April 1944 to the complete liberation of France, her 7,000 maquisards fought 22,000 SS soldiers, causing 1,400 casualties, while taking only 100 themselves. Her French companions, especially Henri Tardivat, praised her fighting spirit; amply demonstrated when she killed an SS sentry with her bare hands to prevent him raising the alarm during a raid. During a 1990s television interview, when asked what had happened to the sentry who spotted her, Wake simply drew her finger across her throat. On another occasion, in order to replace codes her wireless operator had been forced to destroy in a German raid, Nancy Wake rode a bicycle for more than 500 miles (800 km) through several German checkpoints.[citation needed]

After the war, she received the George Medal, the United States Presidential Medal of Freedom, the Médaille de la Résistance and thrice the Croix de Guerre. She also learned that the Gestapo had tortured her husband to death in 1943 for refusing to disclose her whereabouts. After the war she worked for the Intelligence Department at the British Air Ministry attached to embassies of Paris and Prague. After marrying John Forward in 1957 she returned to Australia.

Conservative in politics, in the 1949 and 1951 Australian federal elections Wake stood as the Liberal candidate against the opposition leader, Labor's H.V. Evatt, for the Sydney seat of Barton. She narrowly lost both. In the former election she recorded a 13 per cent swing against Evatt. In the 1958 election, there was a 2.9% swing against him. Barton was now a very marginal seat, and rather than risk facing Wake again, Evatt moved to the safe seat of Hunter. In 1966 she once more ventured into politics, on this occasion standing as the Liberal candidate for the Sydney seat of Kingsford Smith. Again, despite recording a swing of 6.9% against the sitting Labor candidate, she was unsuccessful.[citation needed]

Nancy Wake was appointed a Chevalier of the Legion of Honour in 1970. In 1985, Wake wrote her autobiography The White Mouse. In 1988 the French Government promoted her to Officer of the Legion of Honour. John Forward died in 1997; the couple had no children.

In February 2004, she was made a Companion of the Order of Australia. In April 2006, she was awarded the Royal New Zealand Returned and Services' Association's highest honour, the RSA Badge in Gold. Nancy Wake's medals are on display in the Second World War gallery at the Australian War Memorial.

As of 2009, she is living in The Star and Garter Home in Richmond, London.