In some mountain families making "Blackberry Wine" was a tradition.
The wine was usually served only for special occasions.
Gather six to eight gallons of wild blackberries, wash them and put them in a big container. Mix in five pounds of sugar and cover the container with a cloth, fastened securely so that bugs can't get in but the mixture can still breathe. Let sit for eight to ten days.
Then strain the mixture through a clean cloth, squeezing the pulp so that all the juice is removed. Measure how many gallons you have. For every gallon of juice, add one and a half pounds of sugar. Let it work off. When it stops (bubbling has stopped on top), strain it again and measure the juice, adding another one and a half pounds of sugar to each gallon. When it finishes working this second time, bottle it.