Parlare... A vanvera!
«Parlare a vanvera. To talk randomly, regardless of the contents. Temere loqui. Also known as: talking to the wind. Meaning: unfounded».
So wrote the Tuscan polygraphic author Francesco Serdonati, who lived between the sixteenth and seventeenth centuries, at letter "P" of his Proverbs. This means that a vanvera was already tightly bound to the parlare verb at that period.
There are several regional variations of a vanvera, particularly in the areas of Lucca and Pisa, Tuscany. There, a cianfera (Malagoli 1997, s. v.) and bámbera (cfr. Lippi, Malm., VIII 56, quoted by Gherardini, Suppl., s. v.) were recorded. The latter is likely to derive from the spanish card game bambàra.
Thus, a broad range of colorful and pictorial usages exists. That may be due to the vividness of a highly adaptable, rhetorically effective word, thanks to its alliterative style and onomatopoeic origins.
L’Etimologico, dictionary by Nocentini-Parenti, under the term vanvera writes: «voiced consonant variation for fànfera, that derives from the same imitative sequence of fànfano, fanfara e fanfarone» (the last one is from spanish fanfarrón).
One could hence think of a back-formation from fanfarone. Behind that, there would be the fan fan sound, typical of military trumpets, that well harmonizes with the above Serdonati's definition "talking to the wind".
However, a deeper investigation reveals that the ultimate origin is not from Spanish, but from ancient French fanfan (see also the Limousin fanfougnias).
Source: Accademia della Crusca