Shah's were originally Khan (not the muslin khan, but a rajputania chettri of the Chhirttaurgar provinces of northwest India - more likely pronounced खाड with a thoplo on top of खा). anyways, the title of "Shah" was given by Badshah (shah of shahs or Emperor) of New Dehli of the Mugal Dynasty. So, until Prithvi Narayan Shah, they could only write Shah after their name, because they were only King. After King Prithvi, took over many smaller pricipalites and brought kings under him, he did not write BadShah, since BadShaha is written only by Muslim rulers, so he wrote Maharaja (King of Kings) like the hindus do. So, in brief, the Shah rulers of Nepal are really Hindus. Only the shah rulers after Prithvi Narayan are Maharaja, in the history of Nepal. However, The 8 Rana prime minsters (Bom Bahadur is excepted) also enjoyed the titlte of Maharaja, as Lamjung also had a titular Raja when the Rana PMs were the real rulers (Shree 3 Maharaj) of Lamjung and Kaski.