Metr. Tarasios was born Peter (Panayiotis) C. Anton in Gary, Indiana, on March 16, 1956, to Peter and Angela Anton. The family moved to San Antonio, Texas, in 1960, and young Peter grew up in the Church of St. Sophia. He studied at Hellenic College (B.A.) and Holy Cross Greek Orthodox School of Theology (M.Div.) as well as Trinity University in San Antonio, the University of Notre Dame in Indiana (M.A. in Theology 1983), the Pontifical Oriental Institute in Rome, and the Pontifical School of Paleography and Archives at the Vatican. He served as a lay assistant at St. Nicholas Greek Orthodox Church in St. Louis, Missouri, beginning in 1980 and in 1988 was appointed the Administrative Assistant of the Diocese of Atlanta.

In 1990, Peter became the first Greek American to serve at the Patriarchal court in Constantinople, when he was invited by the Ecumenical Patriarch Demetrios of blessed memory. He was ordained to the diaconate by Metr. Bartholemew of Chalcedon given the name Tarasios in honor of Ecumenical Patriarch Tarasios of Constantinople and President of the 7th Ecumenical Council. Having advanced through the ranks of the patriarchate, he achieved the rank of Grand Archdeacon to Ecumenical Patriarch Bartholomew. In this role he accompanied His All Holiness on many Patriarchal visits around the globe while overseeing the operation of the Patriarchal Church of St. George (the seat of the Ecumenical Patriarch) and various functions of the Archdiocese of Constantinople. He represented the Patriarch on many occasions and was actively engaged in public relations and established the English Language Department to the Chief Secretariat of the Patriarchate. Most successfully, he co-organized and coordinated international environmental conferences and symposiums held under the auspices of the Patriarchate.

He was elected Metropolitan-Archbishop of Buenos Aires, Primate and Exarch of South America on May 8, 2001, ordained to the priesthood on May 27, in Prokopi (present day Ürgüp, Turkey), ordained to the episcopate on June 3 in Constantinople and was enthroned in Buenos Aires on July 14, 2001.

Metr. Tarasios speaks English, Greek, Spanish, Italian, and French, and has some reading and fundamental knowledge of Portuguese and Turkish.

He established close ties with the inter-religious communities primarily of Buenos Aires but also throughout the South American continent, except for Colombia and Venezuela.

On November 29, 2019, the Holy and Sacred Synod of the Ecumenical Patriarchate elected Metr. Tarasios to the Metropolitanate of Rhodopolis , Primate and Exarch of Lazica and at the same time recommended his assignment to the Patriarch Athenagoras Orthodox Institute in Berkeley, California.