Iraq in the tenth and eleventh centuries witnessed a flowering of Shiite cultural production with lasting effects on the Islamic sciences such as law, hadith, theology, and Qur'anic commentary. The works of al-Shaykh al-Mufīd (d. 413/1022), al-Sharīf al-Murtaḍā (d. 436/1044), and al-Shaykh al-Ṭūsī (d. 460/1067) not only broke significant new ground in Shiite intellectual history and defended Shiite doctrinal positions against opponents, but also set parameters for production in these fields that would remain in effect, grosso modo, until modern times. During the same period, Shiite authors made substantial contributions to fields not directly related to Shiite religious doctrine, playing a crucial role in elaborating and preserving Islamic heritage in general. Al-Masʿūdī's (d. 345/956) famous history Murūj al-dhahab and Abū al-Faraj al-Iṣfahānī's (d. 356/967) collection of songs, poetry, and associated lore, Kitāb al-Aghānī, are prominent examples of Shiite authors' contributions to general Arabo-Islamic cultural production. Arguably yet more important is the Fihrist, composed in Baghdad in 377-378 ah/987-988 ce by Ibn al-Nadīm, an Imāmī Shiite bookseller. This work, a comprehensive catalogue of Arabic book titles, is widely recognised as one of the most important sources for the history of all learned disciplines recorded in Arabic in the course of the first four Islamic centuries. As a consequence, the present understanding of entire swaths of Islamic intellectual history, including the rise and development of Muʿtazilī theology and the translation of the Greek sciences into Arabic, is heavily indebted to a Shiite author.