Taj al-Dawla Ziyar was the Baduspanid ruler (ustandar) of Rustamdar from 1325 to 1333.
He succeeded to the throne after instigating the murder of his predecessor and brother Nasir al-Din Shahriyar through his son Iskandar.
[1] He defeated his brother Izz al-Dawla, who opposed him and had sought support from the Mongol Ilkhanate.
He died in 1333 in Kavir, and was succeeded by his son Jalal al-Dawla Iskandar.
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