Plans for the building of St. Peter Cathedral were initiated in 1873 by Bishop Tobias Mullen of the Roman Catholic Diocese of Erie.

The cornerstone was laid in a formal ceremony held on St. Peter in Chains Day (See General Roman Calendar as in 1954), 1 August 1875.

The architect was Patrick Keeley of Brooklyn, a prolific designer of churches whose works include 21 cathedrals in the eastern United States.

[1][4][5][6] The stained glass in the sanctuary and transept was installed by the Franz Mayer firm of Munich, Germany, and includes depictions of the Annunciation, the Birth of Jesus, the Crucifixion, the Resurrection, the Ascension, and the Second Coming.

Large side windows show the Conferral of Keys to Saint Peter and Jesus' supper at the house of the Publican.