Concordat

A concordat is a convention between the Holy See and a sovereign state that defines the relationship between the Catholic Church and the state in matters that concern both, i.e. the recognition and privileges of the Catholic Church in a particular country and with secular matters that affect church interests.

According to P. W. Brown the use of the term "concordat" does not appear "until the pontificate of Pope Martin V (1413–1431) in a work by Nicholas de Cusa, entitled De Concordantia Catholica". The first concordat dates from 1098, and from then to the beginning of the First World War the Holy See signed 74 concordats. Due to the substantial remapping of Europe that took place after the war, new concordats with legal successor states were necessary. The post-World War I era saw the greatest proliferation of concordats in history.

Although for a time after the Second Vatican Council, which ended in 1965, the term 'concordat' was dropped, it reappeared with the Polish Concordat of 1993 and the Portuguese Concordat of 2004. A different mode of relations between the Vatican and various states is still evolving, often contentiously, in the wake of a growing secularism and religious pluralism in the western world.