The Order of SS. Maurice and Lazarus emerged from the fusion of the Order of St. Maurice, founded under Amadeus VIII, first Duke of Savoy, in 1434 and the Order of Lazarus, founded in Palestine, probably around the year 1060, before the first Crusade. Shortly after, Amadeus VIII was elected anti-pope by the Fathers of the Council of Basel in 1439 and took the name of Felix V. He abdicated in 1449 after recognizing the true Pope Nicholas V (1447-1455).
The aims of the Order of St. Maurice were to serve God, leading a monastic life, and to assist the State in its needs. The choice of its members was very meticulous: they had to be irreproachable in every aspect. Having remained dormant for a long time, Gregory XIII recognized it as a military-religious Order in 1572 and in the following year he authorized the fusion of the Order of St. Lazaraus with it under the rule of St. Augustine, already adopted by the Order of St. Maurice.
The specific object of the Order of St. Lazarus was
to assist the lepers in the Holy Land wherever there was a
particular need of such an apostolate. Its Master was himself
always a leper, and many of the Knights suffered from the same
disease. The Order enjoyed the protection and help of many
Sovereigns and especially Popes, most of all of Clement IV
(1265-1268) .
Compelled to leave the Holy Land in 1291, the Order repaired to the Kingdoms of Naples and Sicily, and of France. Its main seat was the famous St. Lazarus hospital for lepers near Capua from the fifteenth to the sixteenth century. The decline began with the struggle for the Grand Mastership of the Order and the loss of many of its estates. To save the Order from total collapse, Pius II ( 1458-1464) tried to unite it with other Orders in 1459 so as to form the Militia of St. Mary of Bethlehem, but without success. Sixtus IV ( 1471-1484) also tried to fuse it with the Order of St. John at Jerusalem, but likewise in vain. Finally united with the Order of St. Maurice with the full support of the papacy, it assumed a hospitaller and military character adding to its original aim, that of the defense of the Holy See. All attempts to persuade the French branch of the Order of St. Lazarus to join in the fusion having failed, this branch was finally united with the Order of Our Lady of Mount Carmel.
The French branch of the Order of St.
Lazarus was introduced into Britain by Roger de Mowbray, who was
created the First Baron Mowbray in 1283 and who founded a St.
Lazarus Hospital for Lepers on his own land near Melton Mowbray.
However, the Order of Our Lady of Mount Carmel and St. Lazarus
was finally abolished in 1830, and the Holy See does not
recognize any Orders operating under the name of St. Lazarus.