The “Order of the Most Holy Trinity,” founded at Cerfroid, Meaux, in 1198 by John of Matha* and Felix of Valois, with approval from Innocent III. Known also as “Mathurins,” they followed an austere form of the Augustinian Rule, wearing a white habit. Devoting themselves to redeeming Christian captives, they took a fourth vow to sacrifice their own liberty if necessary, using one-third of their revenues as ransoms. By the fifteenth century there were 800 houses as collecting centers and hospitals; they were particularly numerous in the British Isles. A reform movement, the “Barefooted Trinitarians,” founded by Juan Bautista of the Immaculate Conception in Spain (1596), is the only surviving body, engaged in education, nursing, and ransoming of Negro slaves. Trinitarian nuns were affiliated from earliest times. The “Barefooted Trinitarian Sisters” date from 1612.