The Armenian Cathedral is one of the most valuable monuments of Lviv, the only city in Europe where three Catholic archbishops (of Latin, Greek and Armenian rites) resided before World War II. It is a unique example of the layering of traditions and styles over almost 600 years.

The oldest part - the cross-dome basilica - was built in the second half of the 14th century on a Greek cross plan, in a style typical of medieval Armenian and Crimean sacred architecture. From the 16th century, the temple was gradually enlarged. The accession of Lviv Armenians to the union with the Holy See in the mid-17th century and the fires that destroyed the cathedral several times in the 17th and 18th centuries contributed to the gradual Latinisation of its interior.

In the course of the 19th century, the small community of Polish Armenians in Eastern Galicia and Bukovina became almost completely Polonised. Voices were then raised questioning the desirability of maintaining religious separateness for them. These tendencies were opposed among others by Father Jozef Teodorowicz (1864-1938), the last Armenian archbishop of Lviv. He undertook the work of rebuilding the cathedral and its immediate surroundings. The main idea behind this project was to restore the temple's "Armenian spirit". The most impressive elements of the interior reconstruction of the cathedral were the wall paintings by Jan Henryk Rosen and the mosaics by Józef Mehoffer.

In Rosen's wall paintings (executed between 1925 and 1929), the faces of the figures bear the features of important people of the Church of the time or of the priests and faithful of the cathedral parish. In the painting "Crucifixion", St Thomas Aquinas has the face of Archbishop Teodorowicz, and St Matthew in the painting "Institution of the Blessed Sacrament" has the face of Father Dionysius Kajetanowicz, the then pastor of the Cathedral parish. The most exciting work is the 'Funeral of St Odilon' (patron saint of the souls of the dead). It is a highly original composition in which the monks carrying the coffin are accompanied by the spirits of the deceased, outlined with a white line.

After the Second World War and the dissolution of the Armenian Rite Archdiocese of Lviv, the cathedral was used as a museum storehouse. In 2000, the cathedral was handed over for use by the Armenian Apostolic Church (which does not recognise the supremacy of the Holy See). Since 2006, restoration work has been underway at the Armenian Cathedral to restore the temple to its former splendour. They are financed by the Ministry of Culture and National Heritage of the Republic of Poland and, since 2018, also by the POLONIKA Institute.