Protestantism is a branch of Christianity that emerged in the 16th century as a reaction to perceived errors, abuses, and discrepancies in the Catholic Church. The movement was led by figures such as Martin Luther and John Calvin, who sought to reform the Church and return to what they saw as the true teachings of the Bible. Key beliefs of Protestantism include:

• Sola fide: Emphasis on the Christian believers justification by God in faith alone, rather than by a combination of faith with good works as in Catholicism.
• Sola gratia: The teaching that salvation comes by divine grace or "unmerited favor" only.
• Priesthood of all believers: The belief that all Christians have equal access to God and do not need an intermediary such as a priest.
• Sola scriptura: The belief that the Bible is the sole infallible source of authority for Christian faith and practice.

Protestantism encompasses numerous denominations, including Methodist, Presbyterian, Lutheran, Baptist, and others. The term "Protestant" originally referred to a member of any Western church that subscribed to the main Protestant principles, but it later became a general term for any adherent of the Reformation in the German-speaking area. Protestants reject the Catholic priesthood system and instead give allegiance to God alone, affirming the giftedness of every follower of Jesus Christ.