A passionate non-believer, Bradlaugh loved to debate the merits of the Bible with fervent, often well-known, believers. He was a courageous and stirring orator and crowds flocked to hear his verbal duels. Some of the public debates were so lengthy they were conducted over several consecutive evenings. Others became heated, and sometimes the authorities tried to stop him speaking. Opponents to secular speakers sometimes tried to trick them into saying something that would be regarded as blasphemous. Some secularist speakers even went to prison for blasphemy. Bradlaugh, however, was ingenious in outwitting his opponents; in the coastal town of Devonport in 1859 he addressed a meeting from a barge just a few feet off-shore so that he would be speaking outside the jurisdiction of the town’s police. Bradlaugh’s oratory was later put to good use in his parliamentary career. He was elected as an MP for Northampton, but was not allowed to take the oath to take his seat in Parliament. A by-election was called, and he was elected again – this process recurred several times until a new Speaker of the House of Commons conceded that he should be allowed to take his seat after making a non-religious affirmation. Legal oaths are also required, for example, in courts and in connection with some legal documents. In 1888 Bradlaugh’s Oaths Act enabled non-religious affirmations to be accepted as an alternative to religious oaths. Before the advent of broadcasting, books and magazines were much widely read than today. So, to spread the word about “secularism”, Bradlaugh wrote books and pamphlets, including A Plea for Atheism (1877), and founded an influential magazine called the National Reformer. Bradlaugh will be best remembered however for having founded the National Secular Society, which he did in 1866, and his pioneering work to make artificial contraception widely available to those of all classes. In 1877 he was tried, with his friend, feminist and socialist, Annie Besant, for publishing a pamphlet supporting birth control. He was sentenced to six months imprisonment and a large fine, but the verdict was overturned on appeal. Without artificial contraception, women frequently bore five or more children, and many were miserable and poverty-stricken because of this. The churches, however, rigorously opposed artificial contraception. The Church of England abandoned this policy in 1930, but the Roman Catholic Church still retains it.

In 1800, Charles Knowlton, M.D. was born in Massachusetts. Freethinkers pioneered the movement to prevent unwanted pregnancies, and Knowlton was one of the earliest of the freethought reformers. He earned his medical degree from Dartmouth College in 1824. He became an ardent foe of the influence of Christianity, writing Elements of Modern Materialism (1829), in which he identified himself as an "infidel." The book challenges the religious dualism of body and spirit, and Knowlton presents a psychological theory that’s been described as “early behaviorism.” Fruits of Philosophy; or, the Private Companion of Young Married People (1832), tackled the subject of birth control before that term existed. Knowlton dispassionately made the case for preventing conception, and promoted a syringe-administered douche. The first edition was anonymous. The book was published in nine U.S. editions, and was reprinted by subscription by a group of doctors at Harvard Medical School in 1877. In the summer of 1829, he took a “one-horse load” of books down to New York city. He failed to sell any, but probably visited local freethinkers like Robert Dale Owen. Knowlton named his second son Stephen Owen, after his father and his friend. Dr. Knowlton was prosecuted and fined at Taunton, Mass., in 1832, and was sentenced to three months' imprisonment at hard labor in the House of Correction in Cambridge in December 1832. He went directly from jail upon his release to a freethought society in Boston run by Abner Kneeland, where he delivered "Two Remarkable Lectures," referring to superstition as the "moral monster." He was unsuccessfully prosecuted in Greenfield, Mass., at the instigation of a minister. Knowlton's groundbreaking work was reprinted in England by various freethought publishers. British atheists Charles Bradlaugh and Annie Besant republished it in 1877 to challenge the Obscene Publications Act. They were prosecuted and tried, narrowly avoiding jail. The case shot the book's circulation from a thousand a year to a quarter million in England. Besant rewrote the dated text into Law of Population in 1879, which became a bestseller and helped to hasten the birth control movement worldwide, but lost her custody of her daughter. Knowlton was considered one of the leading freethinkers of his era. He was a delegate at the Convention of the Infidels of the United States, meeting in New York City in 1845.

Annie Wood Besant (1 October 1847 – 20 September 1933) was a prominent British socialist, theosophist, women's rights activist, writer and orator and supporter of Irish and Indian self-rule. She married aged 20 to Frank Besant, but separated from him over religious differences. She then became a prominent speaker for the National Secular Society (NSS) and writer and a close friend of Charles Bradlaugh. In 1877 they were prosecuted for publishing a book by birth control campaigner Charles Knowlton. The scandal made them famous, and Bradlaugh was elected M.P. for Northampton in 1880. She became involved with union actions including the Bloody Sunday demonstration and the London matchgirls strike of 1888. She was a leading speaker for the Fabian Society and the Marxist Social Democratic Federation (SDF). She was elected to the London School Board for Tower Hamlets, topping the poll even though few women were qualified to vote at that time. In 1890 Besant met Helena Blavatsky and over the next few years her interest in theosophy grew while her interest in secular matters waned. She became a member of the Theosophical Society and a prominent lecturer on the subject. As part of her theosophy-related work, she travelled to India. In 1898 she helped establish the Central Hindu College and in 1922 she helped establish the Hyderabad (Sind) National Collegiate Board in Mumbai,India . In 1902, she established the first overseas Lodge of the International Order of Co-Freemasonry, Le Droit Humain. Over the next few years she established lodges in many parts of the British Empire. In 1907 she became president of the Theosophical Society, whose international headquarters were in Adyar, Madras, (Chennai). She also became involved in politics in India, joining the Indian National Congress. When World War I broke out in 1914, she helped launch the Home Rule League to campaign for democracy in India and dominion status within the Empire. This led to her election as president of the Indian National Congress in late 1917. After the war, she continued to campaign for Indian independence and for the causes of theosophy, until her death in 1933. She fought for the causes she thought were right, starting with freedom of thought, women's rights, secularism (she was a leading member of the National Secular Society alongside Charles Bradlaugh), birth control, Fabian socialism and workers' rights. Once free of Frank Besant and exposed to new currents of thought, she began to question not only her long-held religious beliefs but also the whole of conventional thinking. She began to write attacks on the churches and the way they controlled people's lives. In particular she attacked the status of the Church of England as a state-sponsored faith. Soon she was earning a small weekly wage by writing a column for the National Reformer, the newspaper of the NSS. The NSS stood for a secular state and an end to the special status of Christianity, and allowed her to act as one of its public speakers. Public lectures were very popular entertainment in Victorian times. Besant was a brilliant speaker, and was soon in great demand. Using the railway, she crisscrossed the country, speaking on all of the most important issues of the day, always demanding improvement, reform and freedom. For many years Besant was a friend of the National Secular Society's leader, Charles Bradlaugh. Bradlaugh, a former soldier, had long been separated from his wife; Besant lived with him and his daughters, and they worked together on many issues. He was an atheist and a republican; he was also trying to get elected as Member of Parliament (MP) for Northampton. Besant and Bradlaugh became household names in 1877 when they published a book by the American birth-control campaigner Charles Knowlton. It claimed that working-class families could never be happy until they were able to decide how many children they wanted. It suggested ways to limit the size of their famil