White Men's Medicine
Until the introduction of the birth control pill in 1960, diaphragms and condoms were the primary forms of contraception. Early condoms were probably made from linen sheaths. The cervical cap was introduced in early 1800s, and the diaphragm was introduced later that century. In the mid-nineteenth century, feminists in the United States began a birth control campaign associated with the slogan "Voluntary Motherhood." This campaign advocated birth control by abstinence.
(http://www.sachet.org.ok/gender/womens_health_002.html, Historical Overview of Contraception)
Because of the popularity of the contraception in 1960s, two missionaries from America, Mr. White and Mr. Campbell, in order to civilize the other part of the world, Africa, they settled, with the help of another British Missionary, Mr. Brown, in the land called Umoufia.
Not for a long time did Okonkwo arrive back to his fatherland. Once again in only one market week he woke up in the middle of the night to find himself sweating in his bamboo-bed.
Last time, the first night he came back to Umuofia, the nightmare about his resemblance his father and his exile to his motherland together struck him to spring to a seated-position when the first cock had crowed. But this time, it was not the nightmare that awakened him. Instead, it was the sound from the instrument of the crier. Gome gome gome gome. Then came his message. Every man of Umuofia was asked to gather at the market place tomorrow morning.
"This," Okonkwo thought, fisting, looking absent-mindedly at the mirror opposite of him, " must be about those white skins. I'll show them who I am and WHAT I am. Okonkwo, this is the time, the right time, you gained your respect back." Then he forced himself to sleep.
Next morning came and thousands of people shuffled towards the market place.