The Marcomanni were a Germanic people that established a powerful kingdom north of the Danube, somewhere near modern Bohemia, during the peak of power of the nearby Roman Empire. According to Tacitus and Strabo, they were Suebian.
It is believed their name may derive from Proto-Germanic *markō "border, boundary" (hence the English march or mark, meaning "frontier, border", as in the Welsh marches and the kingdom of Mercia) and *mann- (pl. *manniz) "man", *Markōmanniz, which would have been rendered in Latinised form as Marcomanni.
The Marcomanni first appear in historical records as confederates of the Suebi of Ariovistus fighting against Julius Caesar in Gaul (now France) after they had crossed the Rhine from what is now southern Germany. The exact position of their lands at the time is not known. The fact that their name existed before the Romans had territory near the Danube or Rhine raises the question of which border they lived near to explain their name. Their