Islamist (n.)
1850, "a Muslim," from Islam + -ist. Later also "scholar of Islamic studies." By 1962 specifically as "strict fundamentalist Sunni Muslim." Islamism is attested from 1747 as "the religion of the Muslims, Islam." Islamite "a Muslim" is from 1786 (1768 as an adjective); Islamize/Islamise (v.) is from 1849.