A Roman Catholic monastic order founded by St. Bruno of Cologne in Chartreuse (north of Grenoble, France) in 1084. The Carthusians combine the solitary existence of hermits with a communal life within the monastery. The monks or nuns live in individual cells and only come together at specific times of the day and at special feasts; strict abstinence is practiced. The Carthusians spread slowly, but, by 1521, the order numbered 195 houses in every Catholic European country. They played an important role in the monastic-reform movement of the 11th and 12th centuries; it is itself, however, the one form of communal religious life that has not experienced reform. Houses are found in many parts of Europe although membership is relatively small. A famous liqueur is made at 'La Grande Chartreuse,' the order's mother-house, with profits donated to charity.