King Clovis: In late 5th century, King Clovis united the Germanic tribe called the Franks, which went all the way from Germany to France. The capital of his empire was in Paris, and he was a Roman Catholic convert. The culture that he helped create would in turn help Europe come together against Muslim invaders, with Charles Martel beating the Muslim army at the Battle of Tours.
Mutual excommunication of Pope of Rome and patriarch of Constantinople: The event in 1054 that led to a complete break in the relationship between the Orthodox religion of Constantinople in the east and the Roman Catholics in the west was the Pope of Rome and the patriarch of Constantinople mutually excommunicating each other. However, many differences led to this final split. Among other things, they fought over the sacrament of communion, how local languages should be used in the church, and the role of icons in worship.
Sufis: The Sufis were some of the best Islamic missionaries. By emphasizing a personal relationship with Allah, they allowed people to have more flexibility in how they chose to worship Allah. The Sufis were pretty tolerant. If people wanted to combine Allah with other beliefs they held, they were allowed to do so, allowing the Sufis to convert many people to the Islamic faith.
The Qur’an: The Qur’an, the sacred scriptures of Islam, help protect women by saying if a man divorced a woman he had to give her dowry back to her, which was different than had previously been the custom. The Qur’an also said that women were equal before Allah and that Infanticide was forbidden, which had previously been rampant in earlier Islamic nations and women were supposed to be treated with more dignity. Though women were still subservient to men, the Qur’an did help women to be safer and more respected in the society. However, the society was still patriarchal, and, with time, this became even more so. Women had—and in some cases still have—little legal rights, and some Islamic societies followed the Mesopotamian and Persian customs of women having to wear veils, which is another example of cultural exchange.
Vladimir: Vladimir was the Russian prince who converted to Orthodox Christianity from the original pagan religion in Kiev. He only converted after contemplating converting to all of the different big monotheisms: Roman Catholicism, Islam, and Judaism.