In 1928 Lewis incorporated The Freethinkers Society and renamed it "The Freethinkers of America" and became its president (a title he would keep for the rest of his life). He later started his own publishing company, the Freethought Press Association, through which he published literature about freethought written by himself and others. Lewis' book "The Bible Unmasked" was published in 1926 and 15000 copies of it were sold. In the 1930s, Lewis expanded his business with a subsidiary, Eugenics Publishing Company, that published literature for common people written by medical experts about subjects such as contraception. Like Haldeman-Julius, Lewis published low-cost books on controversial topics and enjoyed commercial success. Profits from the Eugenics Publishing Company enabled Lewis to live comfortably, with an estate in Westchester County, New York, an apartment on Park Avenue in New York City, and a house in Miami Beach. He was also able to fund the Freethinkers of America's annual deficit; as a result, said freethought historian Robert W. Morrell, "it became in effect his private fiefdom."