Uncle Mac seems almost surprised that a eunuch was both a general and a consul in the Roman Empire. Eutropius was but one of a great many eunuchs who rose to high positions through their military feats or who used their high position as an entry into military matters, though he was the only one to be appointed consul of the empire.
Jacqueline Long, in her analysis of Claudians diatribe against Eutropius, writes,
At this time the Roman Empire was ruled jointly by Theodosius the Greats two sons. The younger, Honorius, reigned in the West, with his court based at Milan; the elder, Arcadius, reigned from his court in Constantinople over the eastern half of the empire. Eutropius was Arcadiuss grand chamberlain, or praepositus sacri cubicula. The post was often held by a eunuch, simply because eunuchs made up much of the emperors private domestic staff, just as they did in the households of private citizens. (Long, J., 1996, pp. 1-2) [see the Bibliography (
http://www.eunuch.org/vbulletin/showthread.php?t=17583) for full publication information.
In 398, Eutropius led an army that repelled invading Huns from Armenia, a province of Rome.
More important than Eutropius, though, was Narses, a eunuch general from Armenia who defeated the Ostrogoth Kingdom, which then controlled much of Italy, in a series of battles between 551 and 554. After recapturing Rome for the Roman Empire (which, by then, had its capital in Constantinople), he then remained to govern the province for another 12 years. (see Fauber 1990 for a detailed biography of Narses)
Coinflipper brings up Zheng He, the great Chinese admiral. More important, though, in Chinese history was Zheng Hes contemporary Yishiha (fl. 1409-1451) who secured the northern borders of the Ming Empire and extended Chinese rule far into modern Russia. After his military expeditions, he was put in charge of the Liaodong region (modern Shenyang Province in Manchuria) in 1435. He remained in that post for 15 years.
Eunuch generals were far from rare in the ancient world. Many were important in the Assyrian army (where there were entire ranks of eunuch archers as well). Prominent Assyrian families are known to have castrated younger sons to ensure them a secure future career. Judar Pasha, a Spanish eunuch who had been captured and castrated as a small child, lead a Moroccan army across the Sahara Desert to capture the important trading center of Timbuktu for the Saadi Dynasty. Many of the officers in Judar Pashas army were also eunuchs.
Mohammad Khan Qajar, the founder of the Qajar Dynasty that ruled Persia from 1794 to 1925 was a military leader who had been castrated at age 6. He was succeeded by a relative. There are many other examples of eunuch rulers to be found in history including eunuch pharaohs in Egypt and eunuch emperors in various Near Eastern empires. One of the Serbian kingdoms in the Balkan Peninsula was founded by a eunuch, though I havent been able to find my reference note in a quick search of my office.
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