Protestantism is a major branch of Christianity that originated in the 16th-century , a movement led by figures like Martin Luther and John Calvin to reform the Roman Catholic Church. Today, it is a diverse global faith comprising over one billion followers and thousands of denominations, including Baptists , Methodists, Lutherans, and Presbyterians. Core Beliefs
While denominations vary, mainstream Protestantism is unified by the , which summarize its essential theological positions: protestant