In Nancy, she became an apprentice to a tailor at fourteen, but later was registered as a prostitute in 1905. After a soldier accused her of giving him syphilis, she was forced to leave for Paris, where she met and later wed Henry Richer in 1907. He was a rich industrialist who worked at Les Halles.
In 1912, her husband bought himself a plane and she flew it for the first time in 1913. She claimed in the press at the time to have broken the female record for the Le Crotoy–Zurich trip. She actually only flew the plane to Burgundy, whence it was shipped by train to the Zurich countryside, and flew it into Zurich. However, the new record was approved. In 1914, she participated in the founding of L'Union patriotique des aviatrices françaises ("Patriotic Union of French Women Aviators").
Her husband died in World War I in 1916. She became a spy under Captain Georges Ladoux thanks to her lover, a young Russian anarchist. As part of her duties, she became the mistress of von Krohn, the Naval Attaché of the German Navy in Madrid. On their return to France, she discovered that Captain Ladoux was a double agent and he was placed under arrest.
She married Thomas Crompton in 1926. He was the financial director for the Rockefeller Foundation and patron of the restoration of the Petit Trianon. When he died unexpectedly in 1928 in Genève, she moved to Bougival and lived very well.
After being released from prison and restored to the post of commander, Captain Ladoux published his fictionalized Memoires in 1930. The volume about Richard, Marthe Richard, spy in the French service, was mostly an invention. She claimed half of the vast royalties and accepted the advice to write her own memoirs. Under the pseudonym of Richard she published the best seller, My life as a spy in the French service (adapted as a film in 1937) and instantly became a heroine of France. Under media pressure, her lover Édouard Herriot, French Prime Minister at the time, gave the widowed Mme Crompton the Légion d'honneur for Foreign Affairs.
In 1945, now famous as the "heroine of two wars," she was elected to the municipal council of the 4th arrondissement on the MRP ticket. When she was accused of claiming 300,000 francs for the release of a convicted German traitor, her reputation saved her. Also, her many contradictions raised skepticism among some people.
When the MRP wanted to outlaw prostitution, she tried to convince the municipal council, but they refused. Then on December 13, 1945, she presented her plan for the closing of brothels in the IVe arondissement. The proposition was passed, and they were closed within three months. Encouraged, Marthe Richard began a campaign to end prostitution in all of France.
On April 9, 1946, Marcel Roclore, Minister of State, presented the Commission's report on the population and public health, and concluded that closing the brothels was a necessity. Pierre Dominjon proposed a bill for this purpose. The bill, now known as La loi Marthe Richard, was passed with the votes of an alliance of the Christian democrat MRP and the Communists.
On April 13, 1946, the prostitution registry was destroyed and 1,400 brothels were closed, including 180 in Paris. Many brothels were converted into hotels, which prostitutes continued to use. Prostitution was still legal, though many acts surrounding it were made illegal.
A controversy surrounding her nationality came up in 1948. She was English by her marriage to Thomas Crompton (her repatriation was denied in 1937). Thus, her election was illegal as were the votes she had participated in.
Meanwhile, the director of Le Crapouillot, Jean Galtier-Boissière denounced her services to the nation, accusing her of involvement with organized crime, of smuggling jewels, and of covering up crimes. The inspector of national safety, Jacques Delarue, a specialist in false heroes of war, inquired into the accusations, and found them to be false in 1954. She was called La Veuve qui clôt (a pun on Veuve Clicquot) by Antoine Blondin.