Being predominantly political in nature, Liberal Catholicism was distinct from the contemporary theological movement of Modernism. It is also distinct from both the attitude of Catholics who are described as theologically "progressive" or "liberal".
Liberal Catholicism has been defined as "in essence a trend among sincere Catholics to exalt freedom as a primary value and to draw from this consequences in social, political, and religious life, seeking to reconcile the principles on which Christian France was founded with those that derived from the French Revolution".
The movement of Liberal Catholicism was initiated in France by Hugues Felicité Robert de Lamennais with the support of Jean-Baptiste Henri Lacordaire, Charles Forbes René de Montalembert and Olympe-Philippe Gerbet, Bishop of Perpignan, while a parallel movement arose in Belgium, led by François Antoine Marie Constantin de Méan et de Beaurieux, Archbishop of Mechelen, and his vicar general Engelbert Sterckx.
Lamennais founded the newspaper L'Ami de l'Ordre (precursor of today's L'Avenir), the first issue of which appeared on 16 October 1830, with the motto "God and Liberty". The paper was aggressively democratic, demanding rights of local administration, an enlarged suffrage, separation of church and state, universal freedom of conscience, freedom of education, freedom of assembly, and freedom of the press. Styles of worship were to be criticized, improved or abolished in absolute submission to the spiritual, not to the temporal authority.
On 7 December 1830, the editors articulated their demands as follows:
- We firstly ask for the freedom of conscience or the freedom of full universal religion, without distinction as without privilege; and by consequence, in what touches us, we Catholics, for the total separation of church and state... this necessary separation, without which there would exist for Catholics no religious freedom, implies, for a part, the suppression of the ecclesiastical budget, and we have fully recognized this; for another part, the absolute independence of the clergy in the spiritual order... Just as there can be nothing religious today in politics there must be nothing political in religion.
- We ask, secondly, for freedom of education, because it is a natural right, and thus to say, the first freedom of the family; because there exists without it neither religious freedom nor freedom of expression.
With the help of Montalembert, Lammenais founded the Agence générale pour la défense de la liberté religieuse, which became a far-reaching organization with agents throughout France who monitored violations of religious freedom. As a result, the periodical's career was stormy and its circulation opposed by conservative bishops. In response, Lamennais, Montalembert and Lacordaire suspended their work and in November 1831 set out to Rome to obtain the approval of Pope Gregory XVI. They were received in audience, but after they had left Rome, the 1832 encyclical Mirari vos condemned religious pluralism in general and certain of Lamennais's ideas advanced in L'Avenir without mentioning his name. After this, Lamennais and his two lieutenants declared that out of deference to the pope they would not resume the publication of L'Avenir and dissolved the Agence générale as well. Lamennais soon distanced himself from the Catholic Church, which was a blow to the credibility of the Liberal Catholic movement, and the other two moderated their tone, but still campaigned for liberty of religious education and liberty of association.
The National Congress of Belgium, an alliance between Catholics and secular liberals on the basis of mutually recognized rights and freedoms, adopted in 1831 a constitution that enshrined several of the freedoms for which Liberal Catholicism campaigned. The Congress Column in Brussels, erected in honour of the Congress has at its base four bronze statues that represent the four basic freedoms enshrined in the constitution: freedom of religion, freedom of association, education and freedom of the press. These four freedoms are also reflected in the names of the four streets that lead to the Place de la Liberté/Vrijheidsplein (Freedom Square) of Brussels: the Rue des Cultes/Eredienststraat (Religion Street), the Rue de l'Association/Verenigingsstraat (Association Street), the Rue de l'Enseignement/Onderrichtstraat (Education Street) and the Rue de la Presse/Drukpersstraat (Press Street). The constitution adopted almost all of Lamennais's proposals for the separation of church and state, granting the Catholic Church independence in church appointments and public activities, and almost complete supervision of Catholic education.
- Catholic social teaching
- Christian democracy
- Christianity and politics
- Christian libertarianism
- Modernism (Roman Catholicism)
- Political Catholicism
- Rerum novarum
- Social justice
- "Essentiellement une tendance, chez des catholiques sincères, à exalter la liberté comme valeur première avec les conséquences que cela entraîne pour les principes qui régissent la vie sociale, politique et religieuse : on en vient à vouloir concilier des inconciliables, les principes sur lesquels étaient fondés la France chrétienne et ceux qui découlent de la Révolution" (Arnaud de Lassus, Connaissance élémentaire du Libéralisme catholique, 1988).
- J. P. T. Bury, The New Cambridge Modern History: The Zenith of European Power, 1830-70 (Cambridge University Press 1960 ISBN 978-0-521-04548-3), p. 77
- Parker Thomas Moon, The Labor Problem and the Social Catholic Movement in France (Macmillan 1921), pp. 32-34
- Stuart Joseph Woolf, A History of Italy, 1700-1860 (Routledge 1979 ISBN 978-0-416-80880-3), p. 339
- Ellen Lovell Evans, The cross and the Ballot (Brill Academic Publishers 1999 ISBN 978-0-391-04095-3), p. 25
- Mikuláš Teich, Roy Porter, The National Question in Europe in Historical Context (Cambridge University Press 1993 ISBN 978-0-521-36713-4), p. 86
- Paul Ginsborg, Daniele Manin and the Venetian revolution of 1848-49 (Cambridge University Press 1979 ISBN 978-0-521-22077-4), p. 49