E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
A regiment of 10,000 choice foot-soldiers, which constituted the body-guard of the Persian kings. There was also an army so named at Constantinople, according to Ducange, first embodied by Major Ducas.
The 76th Foot were called The Immortals, because so many were wounded, but not killed, in Hindûstan (17881806). This regiment, with the old 33rd, now form the two battalions of the West Riding.