Complex sentence: Saint Andrews School for Mountain Boys was run by Episcopal monks affiliated with the Order of the Holy Cross, and it was there that Agee's lifelong friendship with an Episcopal priest, Father James Harold Flye, began in 1919.
Split into simpler sentences: Saint Andrews School for Mountain Boys was run by Episcopal monks affiliated with the Order of the Holy Cross. It was there that Agee's lifelong friendship with Episcopal priest Father James Harold Flye began in 1919.