His Eminence, the Most Reverend Gregory (Borishkevitch) was a hierarch of the Russian Orthodox Church Outside of Russia and the first ruling bishop of the Diocese of Chicago and Detroit (now the Diocese of Chicago and Mid-America).
George Ioannevich Borishkevitch was born on April 18, 1889 to Ioann and Juliana Borishkevitch in the village of Mezhirinsk in the Rovno district of Volhynia. After graduating from the local church high school in 1904, he attended the seminary of the Diocese of Volhynia. After graduating from the seminary, he continued his education at the Kazan Theological Academy from which graduated in July 1914 with a Candidate of Theology (Master's degree).
After his graduation from the Kazan Academy, George was tonsured a reader by Archbishop Evolgy (Georgievich) of the Diocese of Volhynia. As a reader, George served at St. Paul's Church in Zhitomir. After his marriage to Angelina Vassilievna Zagorovkaia, George was ordained a deacon on January 30, 1916 by Bp. Thaddeus (Uspensky) of Vladimir-Volhynia. On February 2, 1916, Dn. George was ordained a priest by Abp. Evlogy (Georgievich). After his ordination Fr. George filled a number of teaching and administrative positions in the schools of the diocese, including the Women's Diocesan High School, Kremenets High School, and the diocesan seminary. As a teacher he taught the Law of God, liturgics, Russian language, and Russian history.
In 1920, Fr. George's wife, Angelina, died, and he was assigned as parish priest of the Church of St. John the Theologian in Borisovitch. As a fall out of the upheavals of World War I, the bolshevik revolution, the Russian Civil war, and the border war with the new Polish state, much of the Diocese of Volhynia, and Fr, George, found itself within the borders of Poland.
With the re-establishment of an independent Poland, the issue of the status of the Orthodox Christians in Poland was settled with the establishment of an autonomous Church of Poland in November 1924. With the establishment of the autonomous church, Metr. Dionisy (Waledinsky) appointed Fr. George as dean over a number of parishes in the Polish Orthodox Church. In 1927, Fr. George was appointed rector of the Vladimir-Volhynsky Cathedral. Then in 1932, Fr. George was appointed rector of Kremenets Cathedral. On January 1, 1939, Fr. George was appointed the rector of the Holy Protection Cathedral in Grodno.
While the Germans allowed religious freedom after they invaded the Soviet Union in June 1941, they attempted to encourage nationalism among the Byelorussians and encouraged them to form a Byelorussian Autocephalous Orthodox Church. However, the hierarchs of Byelorussia resisted and an autocephalous church was not formed. Freeing itself from the bolshevik controlled Moscow Patriarchate, the Byelorussians established contact with the Russian Church Outside Russia and cooperated with it whenever possible. The senior Hierarch in the Byelorussian Autonomous Church was Metr. Panteleimon (Rozhnovsky) of Minsk and All Byelorussia.
In 1942, upon the recommendation of Abp. Benedict (Bokovsky) of Grodno of the Mitred Proto Presbyter George Borishkevitch as a candidate for the episcopate of the Byelorussian Church, Fr. George was tonsured a monk with the name Gregory and elevated to the rank of archimandrite. On October 24, 1943, during a meeting of the Council of Bishops of the Russian Orthodox Church Outside Russia in Vienna, Austria, that included hierarchs from the free parts of Byelorussia and Ukraine, Archim. Gregory was consecrated Bishop of Gomel and Mozirsk for the Byelorussian Orthodox Church. The first hierarch ROCOR Metr. Anastassy (Gribanovsky) presided at the consecration assisted by Metr. Seraphim (Lukianov) of Paris, Metr. Seraphim (Lade) of Berlin, and Bps. Sergei (Korolev) of Prague, Benedict of Grodno, Vassily (Pavlovsky) of Vienna, and Philip (von Gardner) of Potsdam.
In June 1944, Bp. Gregory, with the episcopate of the Byelorussian Church fled west ahead of the advancing Soviet Army. In exile the hierarchy of the Byelorussian Church worked closely with ROCOR. After the war had ended, the Byelorussian hierarchy decided in early 1946 that joining ROCOR was their only possible course of action. At a meeting of the Council of Bishops in April 1946, the hierarchs of the Byelorussian Church, including Bp. Gregory, were received as part of ROCOR.
Initially, after his reception into ROCOR, Bp. Gregory served as Bishop of Bamberg, vicar of the Diocese of Berlin and Germany. In 1947, he was appointed Bishop of Montreal and Eastern Canada. In 1950, Bp. Gregory was made a member of the Holy Synod. In 1952, he was elevated to archbishop.
In 1954, the ROCOR Synod of Bishops established the Diocese of Chicago and Cleveland and appointed Abp. Gregory as the ruling bishop. He was active in the life of the new diocese, consecrating a number of new churches including, in 1954, Holy Trinity Church in Milwaukee, Wisconsin, in 1955 St. Sergius Cathedral in Cleveland, Ohio, and St. Panteleimon Church in Minneapolis, Minnesota in 1956.
Upon the repose of Abp. Ieronim (Cherov) of Detroit and Flint in 1957, his small diocese of four parishes was merged into the Diocese of Chicago. With the merger, Abp. Gregory's title became "of Chicago, Detroit, and Midwest America".
In 1957, Abp. Gregory was diagonsed as having cancer. On October 26, 1957, Abp. Gregory reposed, two days after the fourteenth anniversry of his consecration to the episcopate. He was buried at Holy Trinity Monastery in Jordanville, New York, behind Holy Cross Cathedral.