Archbishop Rajič is the successor to Cardinal Emil Paul Tscherrig (77), whom the Holy Father elevated to the College of Cardinals last year, as nuncio to Italy and San Marino.

The Italian Bishops’ Conference thanked Pope Francis for the appointment of the new nuncio, emphasizing the special bond of unity between the Holy See and the Church in Italy. In a press release, the Italian bishops also thanked the previous nuncio, Cardinal Tscherrig, and Msgr. Rajič, who will henceforth serve as nuncio, entrusting his mission to the patron saints of Italy: St. Francis of Assisi and St. Catherine of Siena.

Msgr. Petar Antun Rajič was born to Liberan and Dominika née Mustapić into a Croatian family in Toronto on June 12, 1959.

He was ordained a priest on the Feast of SS. Peter and Paul, June 29, 1987, in the cathedral in Mostar, the Diocese of Trebinje-Mrkan.

After serving for two years, 1987–1989, as the parish vicar in Toronto, he went to Rome, where he stayed from 1989 to 1991 at the Pontifical College of St. Jerome. While in Rome, he attended the Pontifical Ecclesiastical Academy for training in diplomacy. In 1993, he earned a doctorate in canon law at the Pontifical Lateran University. That same year, he entered the diplomatic service of the Holy See.

He served as secretary in the Pontifical Representation in Iran (1993–1996), and in Lithuania, Estonia and Latvia (1996–1998).  He was also the secretary of the Substitute State Secretary of the Holy See, Msgr. Giovanni Battista Re. Since 2003, at the Prefecture of the Papal Household, he has participated in the organization of the Holy Father’s general and private audiences.

On December 2, 2009, Pope Benedict XVI named him Titular Archbishop of Sarsenterum and Apostolic Nuncio to Kuwait, Bahrain and Qatar, as well as Apostolic Delegate to the Arabian Peninsula.

He was ordained bishop on January 23, 2010, in the cathedral in Mostar by Cardinal Secretary of State Tarcisio Bertone.

On March 27, 2010, he was named Apostolic Nuncio to the Repubic of Yemen and the United Arab Emirates. On June 15, 2015, Pope Francis named him Apostolic Nuncio to the Republic of Angola and the Democratic Republic of São Tomé and Principe.  On June 15, 2019, Pope Francis named him Apostolic Nuncio to the Republic of Lithuania, adding the responsibilities of Estonia and Latvia on August 6 of that year.

In addition to English and Croatian, Msgr. Rajič speaks French, Italian and Spanish.