1530s "of or pertaining to the gospel" (adj.), also "a Protestant," especially a German one (n.); with -al (1) + evangelic (early 15c.), from Old French evangelique, from Late Latin evangelicus, from evangelista (see evangelist).
From mid-18c. in reference to a tendency or school in Protestantism seeking to promote conversion and emphasizing salvation by faith, the sacrifice of Christ, and a strictly religious life. As "member of the 'evangelical' party in a church" from 1804. Related: Evangelically; Evangelicalism (1812).