-Green: Province of Marcomannia
-Purple: Province of Sarmatia
-Blue: Other lands that may have been included in either province
These are Roman provinces that Marcus Aurelius may have wanted to annex into the Empire. This is not an exact map as this topic is very obscure, and while we know where the various tribes were in, their exact borders and places were not well known
The Marcomannic Wars were a famous but obscure period where Marcus Aurelius fought and defeated several barbarian tribes along the Empire's borders. The main opponents were the Marcomanni, the Quadi, and the Iazyges. However, there were other tribes mentioned by the Historia Augusta (an unreliable source that I only gave credit to because the early books of the Historia Augusta are more accurate than the rest of the source) and more importantly Cassius Dio. They include the Buri, Hasdingi Vandals, the Lacringi (possibly another Vandal tribe), the Cotini, Hermunduri, and various Free Dacian Tribes.
The main claim for this is the Historia Augusta, which states in Part 2 of the Life of Marcus Aurelius, pg 193-194
"He wished to make a province of Marcomannia and likewise of Sarmatia, and he would have done so had not Avidius Cassius just then raised a rebellion in the East." and on pg. 201
"For three years thereafter he waged war with the Marcomanni, the Hermunduri, the Sarmatians, and the Quadi, and had he lived a year longer he would have made these regions provinces." While this statement is very bold, it does have some small sentiments from a more reliable quote from Cassius Dio, stating in Book 72 pg 62
"Now if Marcus had lived longer, he would have subdued that entire region; but as it was, he passed away on the seventeenth of March, not as a result of the disease from which he still suffered, but by the act of his physicians, as I have been plainly told, who wished to do Commodus a favour."
While Dio's quote is very obscure and that "subdued" could mean a variety of things, many historians and Romaboos have seen these quotations that Marcus Aurelius intended to expand the Empire into these lands and annex them.
There is also some other supporting evidence, such as the fact that Marcus Aurelius never actually finished his wars, explained by the quotes talking about him living longer and subduing the tribes. Commodus is actually the one who brought the wars to an end, and he withdrew entirely from the region, with the tribes reverting back to being client states. They also built plenty of castras and camps in the territories, indicating that they may have been there to stay. Tribal entities in the Roman Empire and Republic often remained in place, such as in Gaul, making it likely that Marcus may have also intended to annex their lands in a traditional Roman fashion. However, despite this, textual evidence does not completely support this, and there are few other primary sources who state this.
It does bring up some related questions though:
Was this a smart strategic move in the long run?
Would this have led to other conquests, maybe a second attempt in Germania or perhaps even in Poland?
Would a second teutoberg occur?
Was Commodus actually a genius, and not a psycho-coward-degenerate that Cassius Dio and every secondary source says he is?
Is the Historia Augusti the MOST ACCURATE source on Roman History?
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