May 20 - Eastern Orthodox Church calendar - May 22
All fixed commemorations below celebrated on June 3 by Orthodox Churches on the Old Calendar.
For May 21st, Orthodox Churches on the Old Calendar commemorate the Saints listed on May 8.
Holy Equals-to-the-Apostles Emperor Constantine (337), and Empress Helena, his mother (327)
Martyrs Polyeuctus, Victorinus, and Donatus, at Caesarea in Cappadocia.
Hieromartyr Secundus and those with him, in Alexandria (356)
Saint Adelphios, Bishop of Onouphis, in Byzantine Egypt (c. 362, or c. 431)
Saint Boros, monk.
Saint Christopher I, Patriarch of Antioch (967)
Hieromartyrs Timothy, Polius and Eutychius, deacons, in Mauretania Caesariensis (Morocco).
Hieromartyr Valens and Companions, Bishop who was martyred in Auxerre in France along with three children.
Martyr Secundinus, in Cordoba in Spain under Diocletian (c. 306)
Saint Hospitius the Hermit of Nice, Wonderworker (581)
Saint Barrfoin (Bairrfhionn, Barrindus) of Killbarron (6th century)
Saint Gollen (Collen, Colan) of Denbighshire, a saint who has given his name to Llangollen in Wales (7th century)
Saint Isberga (Itisberga) of Aire, reputed sister of Charlemagne, nun at Aire (Aria) in the Artois, of which she is the patroness (c. 800)
Saint Ageranus (Ayran, Ayrman) of Beze, a monk at Bèze in France, martyred by the Vikings (888)
Saint Theobald (Thibaud), Archbishop of Vienne (970-1001)
Blessed Constantine (Yaroslav), prince, and his children Michael and Theodore, Wonderworkers of Murom (1129)
Saint Cyril II (Kirill), Bishop of Rostov (1262)
Saint Basil of Ryazan, Bishop (1295)
Saint Helen of Decani, Serbia, Princess (c. 1350)
Venerable Cassian the Greek, monk of Uglich, Wonderworker (1504)
Saint Agapitus of Markushev (Vologda) the Hieromartyr, Abbot (1584)
Saint Constantine the Fool-for-Christ, of Novotorzanin, Russia (c. 16th century)
New Martyrs King Constantine Brancoveanu of Wallachia and his four sons Constantine, Stephen, Radu, and Matthew, and his counsellor Ianache (1714)
Martyr Pachomios of Patmos (1730)
New Martyrs and Confessors
Synaxis of Hieromartyrs of Karelia.
Synaxis of Hieromartyrs of Ufa.
Uncovering of the relics (1998) of St. Andrew Ogorodnikov, fool-for-Christ of Simbirsk (1841)
Repose of Elena Pavlova of Chepel, Kharkov (1885)
Repose of Elder Isaac of Dionysiou Monastery of Mount Athos (1932)
Synaxis of the "Vladimir" Icon of the Most Holy Theotokos (1521)
Synaxis of the "Virgin of Tenderness" Icon of the Most Holy Theotokos from Pskov-Pechersk (1524)
May 21 (Eastern Orthodox liturgics) Wikipedia (Text) CC BY-SA