I recently started reading up on roman legions and found a discrepancy in the historical record on the origin of Legio I Germanica.I usually start with Wikipedia pages on each Legion and then try to gather more information from more academic articles/books.In this case the Wikipedia page on Legio I Germanica states:
"The most favored is that it was raised by Julius Caesar in 48 BC to fight in the civil war against Pompey."
Next when reading LEGIONS OF ROME by Stephan Dando-Collins I noticed that on p78 when discussing Legio I Germanica he starts off with:
"The 1st was Pompey the Great’s most elite and loyal legion, fighting against Caesar in the major civil war battles at Pharsalus, Thapsus and Munda."
I was immediately suspicious of the Wikipedia page since they can be unreliable, and besides that the Legions of Rome book has a lot more citations. This spurned me on the start researching the Legion even more and investigating the battle of Pharsalus especially. Upon reading this article I noted that on page 4 the author states that:
"Caesar, having approached the camp of Pompey, observed that his line was drawn up as follows: On the left wing were the two legions which had been handed over by Caesar at the beginning of the civil strife by decree of the senate, one of which was called the First and the other the Third. At that place was Pompey himself. Scipio occupied the middle of the line with the Syrian legions."
This quote is cited directly from Caesars own account of the battle. That said on several occasions in that article and on other sources (even images of the battle) the 1st and 3rd legion were present on the left wing under the direct command of Pompey.
From what I understand so far it seems like the legion was first raised as a consular legion by Caesar and then given back to the Senate on their request and subsequently handed over to Pompey. With that in mind it seems that both of my initial sources are incorrect in some way: Wikipedia in stating that the legion fought for Caesar and the Legions of Rome in stating that the legion was recruited by Pompey. Although on the later part I might be making assumptions since it states the foundation of the legion "Stemmed from Pompey the Great’s most elite legion" (p78).
What I would like is some clarification on the founding of this legion especially who raised it. So far I have had no success in searching for clarification in academic articles (mostly due to my lack of great books on the subject and Googles inability to provide good articles). This especially bothers me since the main page that pops up on this subject might be wrong and I would like to correct it. I have already marked some lines as requiring citation in the Wikipedia article.
PS this is my first time posting on this sub-reddit, so I am sorry if I have not followed all of the rules about posting here. I will gladly adjust anything that is wrong.
Legio I of Ceasar and Legio I of Pompey are simply two different legions. As they were raising forces independently, each commander has his own numbering system.
Problem here is mostly lack of written sources: even the long standing legions get only the sporadic mentions a la "participated in this campaign, stationed in that province" with decades and centuries long gaps between even such thin mentions. In fact, at this point were know more about some Roman legions and they'r activities from archaeology than traditional sources (Legio VIIII Hispana is probably most famous example).
Pompey's First get's a bit more mentioned because this legion served under Caesar in Gaul between 53 and 50 BC (Jerome Carcopino proposed that during it's service under Ceasar legion was renamed to avoid confusion with Germanica, only a to confusion), so we know from De bello Galico and De bello civili that after returning from Gaul this legion spent winter of 50/49 BC in Capua and was intended to participated in planed campaign against Partians. De Bello Hispaniensi also mentions this legion still being present for the battle of Munda.
That is pretty much entirety of information we have on Pompey's First. And thats quite a lot in comparison- during the Civil War period there was close to 50 legions raised (the highest numbered is Ceasar's XXXXI* I believe), most of them- especially whose who fought on Pompey's side- are lucky to have a single name drop.
*But the existence of this legion known only from single gravestone of the former centurio in this legion, so no thanks to Ceasar or Appian here either.