Your question is a bit off. Arianism is most closely connected with the Goths and their bishop, Ulfilas (ca. 311-383), who translated the New Testament from Greek to Gothic.

In general, the Gothic tribes retained Arianism after the collapse of the Western Roman Empire as a way of distinguishing themselves from their orthodox Nicene christian subjects.

See: History of the Goths by Herwig Wolfram, particularly pp.75-85.