The Carpi or Carpians were a Dacian tribe that were originally located on the Eastern slopes of the Carpathian Mountains, in what is now Bacău county, Romania.
Name
Their name (Carpi) seems to be connected to the place where they lived, meaning "rock" or "mountain" (cf. Albanian karpė='rock', from IE *ker/sker).
Thus the name of the Carpathian mountains is probably either derived from their name, or their name is derived from the name of the mountains. Ptolemy first mentions the Carpates (Karpates) mountain range corresponding to the Western Carpathian mountain range.
History
While most Dacian tribes (such as the Costoboci ) were defeated by the Roman Empire, Carpians increased their power in the 2nd century AD, becoming (until the barbarian invasions) the most important adversaries of the Roman empire in South-Eastern Europe.
Between 238 - 273, allied with the Goths, the Carpians raided the Roman province of Moesia. Becoming a nuisance for the Roman Empire, Diocletian fought them and took the title of "Carpicus Maximus" for defeating them in 297. According to Roman historian Ammianus Marcellinus (Liber XXVIII 1.5), they were moved by Diocletian to Pannonia.
Sextus Aurelius Victor confirms this, but adds that it was the entire Carpian nation that was moved (De Caesaribus, 39:43), although this appears to be infirmed by later attacks of the Byzantine Empire from outside the empire.
Zosimus mentioned them in the 5th century, using the name of Carpo-Dacians (possibly to distinguish them from the Carpians living in the Roman territory), as being defeated at the Danube by Byzantine Theodosius I in late 4th century (Book IV page 114. This was the last chronicle in which the Carpians appear.
Their fate is not known, but it has been suggested that they eventually migrated southward and that they could be the ancestors of Albanians.