According to tradition from the 9th century, Theodore was a stratelate, i.e. the commander of a Roman garrison in Heraklea – today’s Ereğl i – and secretly a Christian. Emperor Licinius came to a victory celebration where many golden statues of pagan gods were erected. Theodore broke them into pieces that he distributed to his arms, revealed himself to Licinius as a Christian and advertised to him that he should be converted. He had him whipped with over a thousand blows, nailed to a cross and shot with arrows, and finally beheaded with the sword. This is how the alleged eyewitness Augarus told it in the story of suffering he wrote. Theodore Stratelates was venerated in Euchanei, a city that was often mistaken for Euchaïta – today’s Beyözü near Amasya – after the victory of the Byzantines over Svjatoslav of Kiev in 971, this city was renamed Theodorupolis in his honor. Since 1166, the feast day of the soldiers was Theodore’s half-day in Byzantium. As a result, the tradition of Theodor Stratelates was combined with that of Theodor Tiro, the Catholic Church venerates them in one person.
Joachim Schäfer: Article Theodor “Stratelates”, from the Ecumenical Dictionary of Saints – https://www.heiligenlexikon.de/BiographienT/Theodor_Stratelates.html