The Renaissance was a movement of "rebirth" beginning in Italy in 1330 and later moving through Northern Europe. During this time, society, philosophies, and art reflected humanism–the ideology that human reason and thought were crucial to society. This movement was also when John Gütenburg developed the movable-type printing press which printed the "Gütenburg Bible." Later in European history, this invention and these ideas were key to the movement of religious ideas and philosophies known as the Protestant Reformation.
The Protestant reformation was kickstarted when Martin Luther posted his "95 Theses" to the church door in Wittenberg. He was tried and deemed guilty of heresy at the Diet of Worms and excommunicated from the Catholic Church. Luther's works that had questioned the Catholic Church and criticized it for its corruption, were printed on the Gutenberg movable-type printing press and spread quickly throughout Europe. Other leaders like Calvin and Zwingli who also questioned the pope's authority, saw Lutheranism as a hope to also break away from the corrupt Catholics.
When Luther first posted the "95 Theses," King Henry VIII of England defended the Catholic Church; however, his relationship changed drastically when he wanted to divorce his wife Catherine of Aragon. The pope denied this request because it was against cannon law. Therefore, King Henry VIII followed in Luther, Calvin, and other leader's footsteps and broke away from the authority of the pope. He divorced Catherine and continued to have 7 different wives, and as a result, was also excommunicated. Then, he created the church of England, now known as the Anglican church, and passed the Act of Supremacy. This law stated that whomever was in charge of the country, was also the head of the church.
The Counter Reformation, also known as the Catholic Reformation, was a movement within the Church where the leaders tried to correct their mistakes before loosing too many people to protestant religions. Pope Paul III, the pope at the time, created the Society of Jesus and the Ursuline Order to educate the people on Church teachings and be counsel members to the country leaders and bring them back to the Catholic Church. Pope Paul III also initiated a counsel between the church leaders to address what changes people sought.
The Counsil of Trent was a gathering of bishops, leaders, and the pope that reformed within the Catholic Church. They focused on clarifying and fixing the things that reformers like Luther and Calvin criticized or did not understand. Luther mainly had an issue with the selling of indulgences to pay your way to heaven. This was addressed. Calvin did not agree with the whole and true presence of Christ in the Eucharist. This was confirmed in Catholic doctrine and was not "fixed" but the way Church leaders taught about it changed and was clarified. Although the abuses that sparked the Protestant Reformation were mostly resolved, and the Church regained many of its followers. However, The Council of Trent did not bring change quickly enough to reunite the religions completely.
The Peace of Augsburg was a temporary treaty within the Holy Roman Empire that allowed each prince to determine his land's central religion. This treaty did not recognize anything other than Catholicism and Lutheranism as a religion, including Calvinism, which upset the rulers who did not follow the pope or Luther. The peace was quickly made to create some religious tolerance, but the loopholes and flaws, like this one, were overlooked at first, but became an issue that caused the rulers to crave religious power.
The 30 Years War was a long lasting war in European history that was caused by the building tension caused by the Peace of Augsburg. Ferdinand II, the Holy Roman Emperor, tried to impose Catholicism on the protestants of Bohemia. Protestant leaders of other countries rebelled against the Holy Roman Emperor and fought on German soil for 30 years. When the Hapsburgs were becoming more and more powerful, the Catholic and Protestant rulers joined forces to weaken Hapsburg rule. In this way, the 30 Years War changed from a religious war to a political one. The people were tired of fighting for "religion" when the war was about power so they called for a treaty of religious tolerance.
The Treaty of Westphalia marked the end of the 30 Years War in Europe. Unlike the Peace of Augsburg, this treaty was developed carefully and with as few loopholes as possible. Besides ending the war and creating lasting religious tolerance, it gave Switzerland independence from Austria, the Netherlands independence from Spain, and Sweden territory and payment for the war. Any hope that the Catholic Church had to reunite the religions was gone and Protestant denominations grew from there.