Iranian aristocrat Ahmad ibn Sahl escaped a prison in Sistan and joined Ismail to defeat and capture Balkh, an ancient center of Buddhism and Zoroastrianism also known as Bactra,
Ahmad ibn Sahl ibn Hashim (died 920) was an Iranian aristocrat who served the Saffarids and later the Samanids. Ahmad, in order to avenge his three brothers, revolted against his overlord, the Saffarid ruler Amr ibn al-Layth (r. 879901), but was defeated and taken prisoner in Sistan. However, he managed to escape and then returned to Merv, where he captured the local governor Abu Ja'far Ghuri and proclaimed his adherence to Samanid ruler Isma'il ibn Ahmad (r. 892-907). In 900 (or 901), Ismail defeated and captured Amr at Balkh, and shortly conquered his territories in Khurasan, which Ahmad also played a role in. It was historically an ancient centre of Buddhism and Zoroastrianism and one of the major cities of Khorasan, since the latter's earliest history. The ancient city of Balkh was known to the Ancient Greeks as Bactra, giving its name to Bactria. 
