Concordat

A concordat is 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 impact on 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 model of relations between the Vatican and various states is still evolving in the wake of the Second Vatican Council's Declaration on Religious Liberty, Dignitatis humanae.

From a Church–State perspective, the contentions regarding Concordats involves two perspectives.

From a Catholic perspective, the Church has the moral and theological right to enter into diplomatic relations with states in order to reach agreements regarding the care of its members residing there. This is the concept of Libertas ecclesiae (freedom of the Church).

However, from a non-Catholic perspective, Catholic church privileges pose certain concerns regarding religious freedom, such as:

Some concordats guarantee the Catholic Church the tax-exempt status of a charity, being by fact the largest charitable institution in the world, either stating this explicitly, as in Brazil (2008, Article 15) and Italy (1984, Article 7.3), or phrasing it indirectly, as in Portugal (2004, art. 12).

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