The Roman Catholic Archdiocese of Santiago del Estero (Latin: Archidioecesis Sancti Iacobi de Estero) is a jurisdiction of the Catholic Church in northern Argentina and the first diocese on territory belonging to the modern Republic of Argentina.

This diocese had its seat at the Church of St. Peter and St. Paul in Santiago del Estero,[1] the oldest city in modern Argentina.

[2][a] Finally, Santiago del Estero became an episcopal seat again on 25 March 1907, when Pope Pius X erected the Diocese of Santiago del Estero covering the entire province of that name, territory taken from the Diocese of Tucumán[2][3] and made a suffragan of the Archdiocese of Buenos Aires.

That title had been assigned pro tempore on 29 January 1936 to the archbishop of Buenos Aires by the decree of the Sacred Congregation of the Consistory Cum Ecclesiastica Provincia Bonaerensis.

[9] In a joint statement, Jorge Ignacio García Cuerva, Archbishop of Buenos Aires, and Vicente Bokalic Iglic, now the Archbishop of Santiago del Estero, noted the title carried no authority and was "honorific", but they said the change "redressed a major grievance in ecclesiastical history".