Cardinal Maurice Piat, Bishop emeritus of Port-Louis, Mauritius. was born in Moka, diocese of Port-Louis, Mauritius, on July 19th 1941. After his secondary studies at the Collège du Saint-Esprit, Quatre-Bornes, Ile Maurice, he entered the novitiate of the Congregation of the Holy Spirit in Ireland, where he made his religious profession on September 8th, 1962. After obtaining a Bachelor's degree from University College, Dublin, he was admitted to the Pontifical French Seminary in Rome and continued his theological studies at the Pontifical Gregorian University, concluding with a licentiate in theology in 1972.

He was ordained a priest on August 2nd, 1970.

In 1972, following his theological studies, he spent three months in the ministry in Bangalore, in India. Upon returning to his homeland he was appointed professor and catechist at the Collège du Saint-Esprit, Quatre-Bornes. Until 1982 he was also responsabile for the aspiring seminarians at the Foyer Monseigneur-Murphy, Vacoas. From 1977 to 1979 he attended a course in Paris at the Institut pour la Formation des Educateurs du Clergé. He returned to Mauritius as vicar in the parish of Saint-François-d’Assise in Pamplemousses (1979-1985) then pastor of the parish Coeur-Immaculé-de-Marie in Rivière-du-Rempart (1986).

From 1981 he was also in charge of diocesan pastoral planning for basic ecclesial communities, and episcopal vicar for the formation and coordination of diocesan pastoral ministry. In those years he contributed to the creation of a training centre in Thabor, Beau-Bassin.

On January 21st, 1991, he was appointed coadjutor of the then-bishop of Port-Louis, Cardinal Jean Margéot, and received episcopal consecration on May 19th of the same year.

On March 13th, 1993 he bacame bishop of Port Louis.

He was president of the Episcopal Conference of the Indian Ocean (C.E.D.O.I.) from 1996 to 2002; from 2013 to September 2016;  and again in 2020.

Since 2000 he has been a member of the Standing Committee of the Symposium of the Episcopal Conferences of Africa and Madagascar (S.C.E.A.M.)

He participated in the XIV Ordinary General Assembly of the Synod of Bishops on the theme: The vocation and the mission of the family in the Church and in the contemporary world (October 2015).

On 19 May 2023 the Holy Father has accepted the resignation from the office of bishop of Port-Louis, Mauritius presented by Cardinal Piat.

Created and proclaimed Cardinal by Pope Francis in the consistory of 19 November 2016, titular church of Santa Teresa al Corso d'Italia.