I am not sure of the earliest date. I can tell you that 'brands' of a sort were common in the LateRoman and Byzantine empire. Merchants would wear rings with stamps on them, usually in the shape of a symbol (like a modern logo although it was often a chi-ro or cross) or a slogan. The Walters Art Museum has a collection of these commercial stamps, one of which reads in Greek 'Drink Good wine' - suggesting it belonged to a wine merchant looking to brand his product

Zildjan

The drum cymbals company is apparently the oldest brand known to man, it was created in the 1600's and still creating drum cymbals to this day.

Edit - spelling.