[2] Mateo Elías Nieves Castillo was born on 21 September 1882 as a sick child to Ramón and Rita and was baptized on the same day due to fears that he would not live for long.

At the time of the government persecution of the Roman Catholic Church he refused to submit and moved to the hillside where he served his parish during the night so as not to be caught.

"[4][5] The beatification cause for the Servant of God commenced in Morelia in October 1957 and concluded its work in June 1959.

The process was ratified in 1992 and the Positio - documentation on his murder being "in odium fidei" - was sent to the Congregation for the Causes of Saints in 1994.

Pope John Paul II approved the decision that Castillo died in hatred of the faith and beatified him on 12 October 1997.