Abd al-Karim b. Hawazin al-Qushayri was born in Rabi' al-Awwal 376 (July 986) in the Ustuwa region near Nishapur; he was a Sufi and a scholar of theology, Qur'anic exegesis, hadith, and jurisprudence. A student of Abu 'Ali al-Daqqaq and al-Sulami, he became a leading intellectual authority in Seljuk-era Nishapur. He authored the famous er-Risala, a foundational text framing Sufism within orthodox Sunni theology, and died in Nishapur in 465/1072.