Definition
Protestantism is the branch of Western Christianity that emerged from the 16th-century Reformation and rejected the authority of the pope and the Roman Catholic Church. The name comes from the "protest" of reform-minded German rulers against efforts to suppress the new teachings.
Protestantism was never a single church. It quickly split into several traditions — Lutheran, Reformed or Calvinist, Anglican, and others — that shared core convictions but differed on worship, organization, and doctrine.
Why it matters
How it works
Protestantism spread less through one institution than through shared principles adopted by many. Reformers in different regions built their own churches, often with the backing of local rulers, while agreeing on broad ideas such as the primacy of scripture and faith.
This decentralized structure made the movement durable and adaptable: it could take root wherever a community embraced its core teachings. It also meant continuous division, as differing interpretations gave rise to ever more denominations over the following centuries.