Diplomatic relations between the Holy See and Poland have existed at the level of Nunciature since 1555, when the first resident diplomatic representative of the Holy See with the rank of Nuncio arrived in Warsaw, to continue the whose of his predecessors of lesser rank. The signing of a concordat at the beginning of that century was an earlier testimony to the existence of even earlier non-residential diplomatic relations between them. With the Third Partition of Poland in 1795, the Polish state ceased to exist, but was revived after the First World War. Diplomatic relations were reestablished in 1919. When Poland was occupied by German forces in the Second World War, the Holy See continued its diplomatic relations with the Polish government-in-exile. There was no longer a nunciature in Warsaw, but the government in exile continued to maintain an embassy to the Holy See until the 1960s. Full diplomatic relations were resumed in 1989, with the appointment of Archbishop Józef Kowalczyk as Nuncio to Poland.
Holy See–Poland relations Wikipedia
The first Nuncio to Poland, appointed in 1555, was Luigi Lippomano. Suffering from ill-health, he left in February 1557. The list of his successors as Nuncios to the Kingdom of Poland and then to the Polish-Lithuanian Commonwealth is given at Apostolic Nuncio to Poland.
The first resident representative to the resurgent Polish state after the First World War was Achille Ratti, the future Pope Pius XI, who was appointed Visitor in April 1918 and Nuncio in 1919. The Nunciature to Poland was classed as a Nunciature of the First Class, the same level as those in Madrid, Paris and Vienna. Archbishop Ratti was soon appointed Archbishop of Milan and left Poland on 4 June 1921. His successor was Archbishop Lorenzo Lauri, whose nomination had been published on 25 May 1921. Lauri negotiated a concordat with the restored Polish state. On 20 December 1926, he was made a cardinal. From June to October 1923 Monsignor Giovanni Battista Montini, the future Pope Paul VI, worked as Secretary at the Warsaw Nunciature. Archbishop Francesco Marmaggi was Nuncio to Poland from 1928 until becoming a cardinal on 16 December 1935. His successor, Archbishop Filippo Cortesi, who was Nuncio to Poland at the outbreak of the Second World War, left Warsaw on 5 September 1939, following the Polish government-in-exile to Bucharest.
Following the resumption of full diplomatic relations on 17 July 1989, Pope John Paul II appointed as the first Nuncio to Poland after half a century Archbishop Józef Kowalczyk on 28 August 1989. He held this post for an exceptionally long time, until on 8 May 2010 he was appointed archbishop of Gniezno and primate of Poland. His successor is Celestino Migliore, appointed on 30 June 2010.