Vehementer Nos

Vehementer Nos was a papal encyclical promulgated by Pope Pius X on February 11, 1906. Occasioned by the French law of 1905 providing for the separation of church and state. Pope Pius X denounced the law, as a unilateral break of the 1801 Concordat.

Prior to the French Revolution of 1789, Roman Catholicism had been the state religion of France, and closely identified with the ancien regime. During the French Revolution, the National Assembly had taken Church properties and issued the Civil Constitution of the Clergy, which made the Church a department of the State, effectively removing it from papal authority. Subsequent laws abolished the traditional Gregorian calendar and Christian holidays. The revolution led to a brief separation of church and state in 1795, ended by Napoleon's re-establishment of the Catholic Church as the state religion with the Concordat of 1801.

While the Concordat restored some ties to the papacy, it was an attempt on Napoleon's part to win favor with Catholics in France and largely favored the state. According to its terms Catholicism was recognized as the religion of the great majority of the French but not the official state religion. While the Papacy had the right to depose bishops, the French government retained the right to nominate them. The state would pay clerical salaries to clergy who swore an oath of allegiance to the state. The Catholic Church also gave up all claims to Church lands confiscated after 1790, but Sunday was reestablished as a "festival", effective Easter Sunday, 18 April 1802.

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