Jayadaman was a Western Kshatrapa ruler, although possibly only a Kshatrapa, rather than a Mahakshatrapa. He was the son of Chastana, and the father of Rudradaman I and Indradaman but he may have pre-deceased Chastana, and never ruled as supreme ruler of the Western Kshatrapas.Political history of ancient India by Hemchandra Raychaudhuri p.260 This is suggested by the fact that Chastana and Rudraman I are known from contemporary Indian inscriptions to have ruled jointly.Malwa through the ages, from the earliest times to 1305 A.D. by Kailash Chand Jain p.371
His diminished title may also have been a consequence of the conquests of the Satavahanas over Kshatrapa territory. He is believed to have reigned around 130 AD.
The coins of Jayadaman were rather crude, most made of copper/potin and square and earlier it was believed that these were the only coins of his issued. We now have conventional silver drachms of two types from his reign.
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