In medieval Europe, associations sprung up to perform spiritual works of mercy for deceased members. These associations would join together in prayer, fasting, and the offering of Masses for the dead. When a member would die, their names would be recorded in a book. The names in this book would be prayed for perpetually. In some towns, the confraternities would erect a chapel next to the town church.
Most Purgatorial Confraternities and Archconfraternities have gone through periods of rising in popularity, then falling out of existence. Some still exist, such as the Archconfraternity of Death and Prayer, founded in Rome in 1538, and the Purgatorial Archconfraternity established in 1840 by the Redemptorists in Rome. While their existence has ebbed and flowed in Europe, Purgatorial societies or confraternities are largely nonexistent in the United States.
Despite the lack of devotions for the Holy Souls in Purgatory, that doesn't mean the need isn't there. All souls in Purgatory are in need of prayers, fasting, and other spiritual works of mercy to release them from Purgatory into Heaven.