Lucius Trebius Germanus was a governor of Roman Britain in 127, and suffect consul with Gaius Calpurnius Flaccus, the proconsul of Cyprus in 123, at an uncertain date. He is known from a military diploma published in 1997 that bears the date 20 August 127.^[1]

Anthony Birley provides further information on Trebius Germanus. He is mentioned in the Digest, which cites a legal decision Trebius Germanus made while governor of an unnamed province, not necessarily Roman Britain, condemning a slave boy to death for failing to call for help when his owner was murdered.^[2] Birley also notes that Trebius Germanus is a member of a small group of three consuls appointed to the office in a ten-year period who share the same gentilicium -- the others being Gaius Trebius Maximus (suffect consul 121 or 122) and Gaius Trebius Sergianus (consul 132) -- while adding Ronald Syme's observations that "'the obscure Trebii... are the first and last consuls of that name'; elsewhere he called them 'a unique and isolated group'".^[3] Birley speculates on the place of origin for these three consulars, finding less prominent Trebii attested in Italy, Spain, Gaul, and Dalmatia, but preferring none of these.^[4]

Birley offers a few more speculations about Trebius Germanus. He suggests that his tenure as governor followed immediately on his predecessor, Aulus Platorius Nepos, and lasted three years from 125 to 127; the military diploma would date from towards the end of his tenure. Birley also suggests that he may be the governor in whose name a broken and now lost inscription found at Bewcastle was made.^[5] Prior to the discovery of this military diploma, Birley had speculated it might have contained the name of the other three governors then attested under Hadrian -- Nepos, Julius Severus, and Mummius Sisenna, or another consular, Gaius Nonius Proculus, who held the consulship in some undetermined nundinium between AD 50 and 150.^[6]