Righteous Prince Theodore of Novgorod, elder brother of Saint Alexander Nevsky.
Prince Theodore was the elder brother of Saint Alexander Nevsky and ruled Novgorod with him as a youth. He died suddenly in 1233 on the eve of his wedding, and his incorrupt relics, discovered later, were venerated at Novgorod.
Feast day
On the New Calendar, Theodore Yaroslavich of Novgorod is commemorated on June 5. Churches on the Old (Julian) Calendar keep the feast on June 18 of the civil calendar.
Also commemorated on June 5

Mark the New Martyr of Chios
Martyr, Μάρκος ο εν Χίω
New Martyr Mark of Smyrna, beheaded on Chios in 1801 after returning to Christ with repentance.
Ten Martyrs of Egypt
Martyr, Δέκα Μάρτυρες εν Αιγύπτω
Holy Martyrs Marcian, Nicander, Hyperechius, Apollonius, Leonides, Arius, Gorgias, Selenias, Irene and Pambo of Egypt.
Boniface of Germany
Hierarch, Βονιφάτιος ο Γερμανίας
Hieromartyr Boniface, apostle of the Germans, archbishop of Mainz, slain by pagans in Frisia.
Christopher and Conon of Rome
Martyr, Χριστόφορος και Κόνων
Holy Martyrs Christopher and Conon, who suffered for Christ at Rome.