Born into a noble family descended from the leading one of the boyars Dimitrie Cantemir, Roshko was baptized in the Eastern Orthodox Church.
His father, Leonid Roshko, served as naval officer and his mother was Maria Alexandrova.
His uncle, father's brother Vladimir Roshko served as an officer of the Crimean Tatar army and participated in the White movement in 1919, being tortured by the Bolsheviks in Nikolaev.
In occupied Paris Roshko assisted Soviet citizens who had escaped from German camps, and the Jews who was in the French Resistance, demobilized from the army with the rank of Major in 1946.
In 1949 at the request of Cardinal Eugene Tisserand he was sent to Brazil to assist in obtaining visas for Russian displaced persons.
In 1955 Roshko was to Moscow, where he met with the Patriarch of the Russian Orthodox Church, Alexy I of Moscow and Chairman of the Department for External Church Relations Metropolitan Nicholas (Yarushevich) and visited the Trinity Lavra of St. Sergius and Yasnaya Polyana.
In 1957 he helped the Dean (religion) of Saint Trinity Parish in Paris Pavel Grechishkin and his successor Alexander Kulik (1911-1966).
In 1978 Roshko was appointed Plenipotentiary Visitator for Congregation for the Oriental Churches in leading Russian Catholic ministry in the world.
Roshko G. Innocent IV and the threat of Mongol invasion : the message of the Pope Daniel of Galicia and Alexander Nevsky / / symbol .