How did the Romans invent wine?

They sometimes put water in their wine

Answer:

As odd as it seems to us today the Romans often added toxic acetate lead to their wine and other foods. The lead was originally added by the use of lead vessels for crushing or processing the grapes (the acids in Grape Juice would dissolve the lead). This dissolved lead acetate made the wine sweeter. Later they came to add "sugar of lead" (now known as lead acetate) for this same purpose. Burnt bread, or what we ,today call burnt toast, was also used to flavor the wine, in additions to herbs and spices.