November 5, 1848 – Born in Mackeysburg, Pennsylvania, to parents Michael and Ellen (McGuire)

November 7, 1848 – Baptized sub conditione because he was not expected to live

1860 – Becomes a shoemaker's apprentice

1869 – At twenty years of age, John partnered with shoemaker Ted Mangan and set off for Denver, Colorado

1873 – John wrote to the novice master at Notre Dame, Father Augustin Louage, C.S.C., to find out if Holy Cross was the community he had been seeking 

July 9, 1874 – John O'Neill joined the Congregation of Holy Cross

September 8, 1874  – John entered the Novitiate on the grounds of the University of Notre Dame

August 15, 1876 – Br. Columba professed Final Vows in Holy Cross

September 13, 1876 – Br. Columba was assigned to Saint Joseph's Orphan Asylum in Lafayette, Indiana

Summer 1885 – Br. Columba returned to Notre Dame and was assigned to the campus shoe shop

1890 – Br. Columba also assumed the responsibility of personal caretaker of Superior General Fr. Edward Sorin, C.S.C.

November 23, 1923 – Br. Columba passes away

October 28, 2021 – The petition for canonization was lodged by Br. Philip Smith, C.S.C.

June 24, 2022 – Formal opening of the cause for canonization of Servant of God Columba O’Neill, C.S.C.