Margaret Sanger continually pushed against obscenity laws and the Comstock Act, which criminalized sending birth control products or information by US Mail. In 1914, a year after separating from her husband William, Sanger published The Woman Rebel, Ben issue serial. The even more controversial Family Limitation soon followed. This illustrated pamphlet provided detailed anatomy drawings along with education on fertility, family planning, and what she coined “birth control”. She was cited in 1915 for violation of postal obscenity laws, and fled the country.
She had reason to be afraid. It was an era hostile to women it saw as immoral: as a divorced obscene socialist, she fit the bill. Perhaps she worried about police brutality and inhumane incarceration. Maybe she feared being committed to an insane asylum, as so many women of the day were, especially in New England. Whatever her specific concerns, Margaret Sanger went to Europe and stayed until she was certain it was safe to return.
There she met with other activists and collaborated on mutual aims. She befriended Marie Stopes, her counterpart in the UK, and learned from compatriots in comparably progressive Denmark about their physical barrier methods. At that point (pre-WWI) contraception in the US was mostly caustic and dangerous douches like Lysol, yes that Lysol, applied after intercourse. They were often ineffective, in addition to causing harm. In Denmark diaphragms and cervical caps provided a natural, low side effect alternative with better success.
Margaret returned to the United States and gave contraception lectures at a variety of churches, women’s leagues, and nursing societies. Notably, she spoke to a woman’s auxiliary chapter of the Ku Klux Klan anti black hate group in Silver Lake, New Jersey. Birth control was her primary concern and Sanger was at best a complicated ally to African Americans and other ethnic minorities.
She embraced the “science” of eugenics and the socioeconomic justifications for legal birth control it provided. However she rejected the foundational racism of eugenics. She believed good genes and bad could be found in all races, and that discouraging childbirth in poverty should be the primary aim of eugenicists. She was also opposed to immigration despite being the daughter of first generation immigrants herself. Sanger supported sterilization of “retards” but objected when Nazis began exterminating disabled people. She donated frequently to the American Council Against Nazi Propaganda.