Hryhoriy Yakhymovych was born on 16 February 1792 in Podborce (today Pidbirtsi), a town in the region of Galicia, a part of the Polish–Lithuanian Commonwealth.

Yakhymovych was appointed as an auxiliary bishop of the Archeparchy of Lviv by Pope Gregory XVI in July 1841 and honored with title of the former see of Pompeiopolis in Cilicia.

He was consecrated on 21 November of that year by the Metropolitan of Galicia (Ruthenian Archbishop of Lemberg) Mykhaylo Levitsky in the Lviv St. George Cathedral.

[3] He was selected on 5 September 1859 and confirmed as the Metropolitan of Lemberg on 23 March 1860, which made him the primate of the Ukrainian Greek Catholic Church.

[citation needed] Hryhoriy Yakhymovych was one of the leading figures of the Ukrainian National Revival in the mid 19th century.