Kayumarth I
| Kayumarth I ملک کیومرث یکم | |
|---|---|
| Malik | |
| Ruler of the Baduspanids | |
| Reign | 1394–1453 |
| Predecessor | Sa'd al-Dawla Tus |
| Successor | Iskandar IV (Kojur) Ka'us II (Nur) |
| Died | 1453 |
| Issue | Iskandar IV Ka'us II |
| Father | Bisutun, son of Iskandar ibn Gustahm ibn Ziyar |
| Religion | Sunni Islam (before 1402–1405) Twelver Shia Islam (after 1402–1405) |
Kayumarth I (also spelled Gayumarth I or Kayumars I; Persian: ملک کیومرث یکم) was the ruler (ustandar) of the Baduspanids from 1394 to 1453, with a three-year interruption. An active expansionist ruler, his kingdom experienced a resurgence during his long reign, which included the reconquest of Rustamdar. He was often at odds with his suzerain, the Timurid ruler Shah Rukh (r. 1405–1447). After his death, a dynastic struggle followed, which resulted in his kingdom being split up by his sons Iskandar IV and Ka'us II, in Kojur and Nur respectively.