CONCORDAT, kon-keedat (concordatum, or, plur., concordata), a compact or conven tion entered into by the Holy See and a secular government to determine their respective powers and rights in the regulation of ecclesi astical affairs within the jurisdiction of the state which is a party to the compact. The earliest example of such compacts is the con vention between Calixtus II and the Emperor Henry V, concluded at Worms in 1122: it marked the end of the great dispute about in vestitures. In 1448 was concluded the so called concordat with the German nation, or with the Emperor Frederic III, under which the patronage of ecclesiastical dignities in the empire was divided between the Imperial Crown and the Holy See.
A more comprehensive compact is that of which the foundation was laid at Constance in 18-48, and subsequently modified by the Frank fort Concordat, and by that of Vienna, which last continued in use till the end of the Holy Roman Empire in 1803. Its place was sup plied, under Pius VII and his successors, by separate concordats with Bavaria, 1817; Prus sia, 1821; Baden, Wiirtemberg and several small states in 1818; Hanover, 1824; Saxony, 1827, and the Netherlands, 1827. A concordat was concluded at Vienna in 1855. Its chief pro visions were that the Pope should have direct communication with the bishops, clergy and people; and archbishops and bishops with their priests and people, and the right to goveru their sees according to the canon law. Educa tion was put under the control of the Church. The bishops were to settle what books should be used. All questions of marriage, except so far as they involved civil consequences, were reserved exclusively to the ecclesiastical courts. The emperor had the power of choosing bish ops, but with the advice of the existing bishops. The Church might acquire new property; but once acquired, it should not he sold or mortgaged without the consent of both Pope and Em peror. In 1868 this concordat was set aside in all the dominions of the Emperor of Austria.
In Italy, an agreement regulating the elec tion of bishops was concluded with Nice and Savoy in 1451, and a formal concordat was made with Sardinia by Benedict XIV in 1740, and with Naples in 1741, and a new concordat was entered Into with Naples by Pius VII in 1818. Charles V of Spain concluded a con cordat with Adrian VI and Clement VII, and a further concordat was made by Clement XII and Philip V in 1737. A concordat with Portugal was made by Benedict XIV in 1741. Memorable is the concordat of 1515 between Leo X and Francis I; the King agreed to annul the pragmatic sanction of Charles VII, which restricted the right of appeal to Rome; and in return the Pope conceded to the king the right of nomination to all Church benefices within the realm, with a reservation of the annates to the Holy See, and with the proviso that the nominees should be acceptable to the Pope. Another celebrated corcordat is that concluded 15 July 1801 between Pius VII and Napoleon ss First Consul; it recognized the legal exist ence of the Catholic Church in France which had been annulled by the Revolution. The eccle siastical topography of France was altered, the number of episcopal sees being reduced from more than 100 to 80. The confiscation of ecclesiastical property by the republican gov ernment was to pass for fait accompli and res judicata and the Pope and his successors were not to move to disturb purchasers or grantees of such properties. The government was to have the right of nomination of bishops, bin the Pope that of canonical institution. Pro vision was to be made by the state for the support of bishops and clergy in lieu of their property, which had been appropriated by the Revolutionary government. Immediately after the concordat was concluded there arose in France an agitation for its abrogation, and this agitation grew more insistent than ever after the Dreyfus affair (q:v.) ancl the Concordat was abrogated finally in 1906.