Ancient civilizations such as Egypt and Mesopotamia developed polytheistic religions that worshipped multiple gods and involved the worship of nature.
The Reformation was a religious movement to reform the practices of the Roman Catholic Church. The Reformation divided Catholics and created beliefs that shaped the modern Catholic Church. The Reformation started with Martin Luther’s "95 Theses," a written protest of what he perceived as the sins of the Pope and leaders of the Catholic Church. The split within the church led to wars and the persecution of those seeking religious freedom from the church. The Reformation ended with the end of the Thirty Year’s War.
The Crusades were a series of wars led by Western European Christian armies. The joint army followed the orders of Pope Urban II to go to war with the Turks to capture Jerusalem and defeat those thought of as enemies of Christianity. The Crusades lasted from 1095 to 1290. These clashes with Muslim and other forces continued until the end of the Ninth Crusade around AD 1290.
The British colonies were founded as an extension of Great Britain, but for the colonists who moved to the colonies, religious freedom from the Church of England was most important. As the colonies began to expand, many of them were founded based upon religious beliefs. For example, William Penn founded the colony of Pennsylvania as a place where Quakers could have a safe place to practice their religion.