Pir Muhammad was born c.1379 and was the eldest son of Umar Shaikh Mirza I by his wife, the Mongol princess Malikat Agha.
His mother, a daughter of the Khan of Moghulistan, Khizr Khoja, was subsequently remarried to Umar Shaikh's younger brother Shah Rukh.
[1] Following his father's death, Pir Muhammad was appointed to his former post as governor of Fars, which had been conquered from the Persian Muzaffarid dynasty by Timur a few years earlier.
[7] Several regional cities, such as Yazd and Abarkuh, quickly declared their support for the prince and some of his advisers urged him to seek the endorsement of the Abbasid Caliph in Egypt.
Pir Muhammad grew alarmed by this and captured Iskandar and seized his territories, though the latter quickly absconded to their brother Rustam in Isfahan.
Rustam instead turned his attention to the eastern regions of Fars and began to plunder them, his forces bolstered by local rulers who had abandoned his brother.
[14] The instigator of the attack was Husayn Sharbatdar, a former pharmacist from the Shiraz bazar whom Pir Muhammad had favoured and raised to the rank of amir.
Wearing only his shirt, a cap and a single boot, the prince mounted his horse and fled to Shiraz, where the city leaders swore allegiance to him.
Sharbatdar himself, having had his beard and eyebrows shaved, was dressed in women's clothing and displayed in public, before being dismembered; his head was kept in Shiraz while his hands and feet were each sent to a different city.