Mary Help of Christians ( Latin : Maria Auxilium Christianorum ) is an invocation of Mary Help of Christians (in the Catholic Church ) created for the Virgin Mary and which bears her name since the year 345 from a homily of Saint John Chrysostom , gained strength with Pope Pius V in the  16th century and was definitively popularized with the development of the educational and apostolic works of Don Bosco and Maria Mazzarello in the  19th century . Although it is commonly associated with the Catholic Church, the Orthodox Church has also known the invocation since 1030 in Ukraine when the country managed to defend itself from a barbarian invasion , a fact that the religiosity of the time attributed to the help of the Virgin Mary. The Catholic Church traditionally commemorates this Marian invocation on May 24.

The invocation of Mary Help of Christians was strongly associated until the  19th century with the military defense of all Catholic and Orthodox strongholds in Europe , North Africa and the Middle East against non-Christian peoples, especially Muslims . Precisely under the pontificate of Pius V, the Euro-Christian peoples gathered a huge force to stop the advance of the Turks who in 1572 led a powerful army with the aim of definitively conquering Europe. While the Christian armies gathered from all European nations managed to definitively defeat the invaders, the Pope had asked all of Christianity to pray and include the invocation Sancta Maria Auxilium Christianorum . With the popularization of the devotion to Mary Help of Christians by the Salesians in all the countries where Don Bosco houses were opened, numerous sanctuaries emerged, among which the most famous is precisely that of the Basilica of Mary Help of Christians in Turin .