The Avanian Catholicosat was functioning in 591-602, in the north-east part of the contemporary Yerevan. It was set up by the Byzantian emperor Mauritius, in contrast to the Dvinian Catholicosat, which was controlled by the Persians.
The Cathoghike church (which was later renamed to St.Hovhannes) was built by Hovhan Bagarantsi in 591. The Avanian Cathoghike is one of the first five-domed churches in the Christian architecture. The Catholicos’ palace adjoins the church from the north.
In 602 the Persian king Khosrov II seized Avan and, having eliminated the Avanian Catholicosat, transformed it into a monastery.