In Der Neue Pauly, s.v. "Vertumnus", Luciana Aigner-Foresti "Urspr. etr. Gott" scribet et deum Voltumnae Etruscae coniunget. In Oxford Classical Dictionary Herbert Jennings Rose et John Scheid rem in dubium vocant, scribentes "supposedly an Etruscan god [...] but nothing confirms this view [...] which may just be speculation based on the resemblance of his name to that of Voltumna and the fact that his temple on the Aventine (its anniversary 13 August) displayed a painting of M. Fulvius Flaccus, conqueror of Volsinii in 264 BC".
