Lombard, with an epicentre in North Milan, derives from the name Vimercate in Milan. Integrations provided by Giovanni Vezzelli the surname Vimercati derives from the toponym of Vimercate, which already appears in a Lombard document of 745 with the form "Vicomercado", a place where a market was held since ancient times. The subsoil of the present Vimercate in this sense has made abundant finds attesting the antiquity of the site, already strong presence in Roman times. The correct form of the name would be Vicomercato, which became Vimercate.
You may be interested
Verba Volant, Scripta Manent