Origin: Hindustani

Proprialisation of raj (“(India) reign, rule”, noun), borrowed from Hindustani राज / راج (rāj, “reign, rule; empire, kingdom; country, state; royalty”), from Sanskrit राज्य (rājyá, “empire, kingdom, realm; kingship, royalty, sovereignty; country”), ultimately from Proto-Indo-European *h₃reǵ- (“to right or straighten oneself; to govern, rule; just; right”). Doublet of Reich.

Etymology: Wiktionary (CC-BY-SA)