Bust of Isvaradatta right, with corrupted Greek legend (Indo-Greek style) / Three-arched hill or Chaitya, with river, two crescents and sun, within legend in Brahmi Rajno Mahaksatrapasa Isvaradattasa varse prathme (Raja Mahakshatrap Isvaradatta year one). 15mm, 2.0 grams. "Studies in the Coinage of Western Kshatrapas" #522.
Isvaradatta appears out of nowhere - it is assumed that he was an army commander who usurped power in a part of the Kshatrapa realm for about two year. On his rare coins he styles himself a "mahakshatrapa", but he does not give his patronimic (without doubt because he did not come from a royal line, a fact to which he did not want to draw attention). He is also the only Mahakshatrapa who did not date his coins in Saka era, but in his own regnal years (this coin shows this date on both sides - "1" on obverse and "year one" on reverse). One of his coins was found dated to 164 SE, but this date was variously read, so the exact year of his reign is still uncertain, though stylistically they fit into the early160's SE period. All his coins are rare.
The Western Kshatrapas, or Western Satraps, (35-405 CE) were Saka rulers of the western and central part of India (Saurashtra and Malwa: modern Gujarat, Maharashtra, Rajasthan and Madhya Pradesh states). They were contemporaneous with the Kushans who ruled the northern part of the Indian subcontinent, and the Satavahana (Andhra) who ruled in Central India.