Saint Demetrius of Thessalonika († c. 306) is one of the most venerated saints of the Christian East, glorified as a great martyr. Demetrius, a native of Thessaloniki, was martyred in the reign of the Emperor Diocletian (284-305), being speared to death in prison. His Feast is celebrated by the Orthodox Church on October 26th (November 8th). In the Greek tradition, he is known as the Myhrbearer, because his relics miraculously produced holy oil. Byzantine texts often refer to him as the Victory-bearer, since the majority of his miracles occurred as aid in time of war. The veneration of the saint made its way to Russia in the 10th -11th centuries, acquiring a special meaning for the Rurikid Dynasty and their court, since St.Demetrius was seen as the patron of warriors and the defender of the realm. After the Battle of the Kulikovo Field (1380), memorial services for the fallen warriors were traditionally held on the nearest Saturday to the Feast of St.Demetrius. Later on, the memorial services started to include all deceased Orthodox Christians and was popularly known as the Demetrius Memorial Saturday.

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