Abu'l-Hasan Ali ibn Fadl ibn Ahmad Isfarayini (Persian: ابوالحسن علی بن فضل بن احمد اسفراینی, died 1013/14), commonly known as Abu'l-Hasan Isfarayini (ابوالحسن اسفراینی), was a Persian[1] vizier of the Ghaznavid sultan Mahmud of Ghazni (r. 998–1030) from 998 to 1010.
During this period the Samanid dynasty was in heavy decline and was struggling for holding control over Khurasan and Transoxiana from several ambitious military leaders who had rebelled against their authority, the most dangerous ones being Fa'iq and the Simjurid Abu 'Ali Simjuri.
Still in 1010/1, Isfarayini managed to raise a considerable amount in Herat, which, however, was not enough for Mahmud, who ordered him to also use his own money to finance the Ghaznavid military campaigns.
Isfarayini, however, disobeyed, and went voluntarily to prison; his property was confiscated and when he was accused of extortion, he was brutally tortured, which resulted in his death in 1013/4.
[2] Isfarayini was succeeded by Ahmad Maymandi, who restored Arabic as the administrate language of the Ghaznavid state.