The Persian alphabet originated directly from the Arabic alphabet, which was introduced to the Persian-speaking world following the Muslim conquest of Persia and the decline of the Sasanian Empire in the 7th century. As a result, Arabic became the primary language of government and religious institutions in Persia, leading to the widespread adoption of the Arabic script. This simultaneous use of Arabic and Persian had an impact on Classical Persian literature and Poetry, influencing them with Arabic elements. Consequently, the Persian language experienced an influx of Arabic vocabulary. In the 8th century, the Tahirid dynasty and Samanid dynasty officially embraced the Arabic script for writing Persian, followed by the Saffarid dynasty in the 9th century, gradually replacing the various Pahlavi scripts previously used for Persian. By the 9th century, the Perso-Arabic alphabet had become the dominant writing system in Greater Khorasan.