During the April 1941 invasion of the Kingdom of Yugoslavia by Nazi Germany, Milan Kovachevich served as a soldier in Serbian Royalist forces who simultaneously battled Hitler, Tito's Communists and Croatian Ustashi during World War II.

When the Allies liberated the military prison camps, he decided not return to his homeland after reading that the Old Regime was usurped by the Communists.

In 1950, he left England for the United States where he earned master's degrees from Saint Vladimir's Orthodox Theological Seminary and Columbia University.

He became a tonsured monk at the Saint Sava Serbian Orthodox Monastery and Seminary in 1953, at which time he chose the name Iriney, meaning "peace" in Greek.

His diocesan headquarters near Third Lake which includes the church of the Protection of the Most Holy Mother of God - New Gracanica, St. Sava Seminary, a monastery, recreational facilities and offices, was consecrated in 1984.