Belgium's Catholic Inheritance and Its Empty Pews

Roman Catholicism is Belgium's historic and largest religion, and around half of Belgians still identify as Catholic in European survey work. But identity and practice have come apart: weekly Mass attendance has fallen into the low single digits. Islam is the second largest religion at roughly seven percent nationally and a far higher share of Brussels, while the fastest-growing category is people with no religion at all.

Catholic on Paper, Empty on Sunday

Two numbers tell the whole Belgian story, and they point in opposite directions. Ask Belgians what they are and a large minority - close to half in recent European Social Survey and Eurobarometer rounds - still answer Catholic. Ask whether they went to Mass last Sunday and the answer, according to the Catholic Church's own annual statistical reports, is a few percent. In the early 1960s roughly half the population attended weekly. That is a fall of well over ninety percent in two generations.

The occasional rituals held on much longer than the weekly ones. Baptism, first communion and church weddings survived as family occasions long after belief had drained out of them, though these too have now slipped: in Flanders the share of newborns baptised has fallen from near-universal to around half or below, and the Church publishes the decline itself each year.

The Recognised Religions System: How Belgium Pays Its Clergy

Belgium does not have separation of church and state in the French or American sense. It has a recognition system, inherited from the Napoleonic settlement and written into the constitution at independence in 1830. The federal state formally recognises a list of religions and, in return, pays the salaries and pensions of their ministers and contributes to buildings and chaplaincies.

The list has grown over time. Catholicism, Protestantism, Judaism and Anglicanism were recognised early. Islam was added in 1974, unusually early for western Europe, and Orthodox Christianity in 1985. In 1993 Belgium did something rarer still and extended equivalent funding to organised non-confessional secular humanism - the laicite and vrijzinnigheid movements - so that people with no religion could draw on state-funded moral counsellors in hospitals, prisons and the army on the same footing as chaplains. Buddhism has more recently been added as a recognised non-confessional life stance.

The practical consequences are large. Belgian state schools must offer pupils a choice between courses in one of the recognised religions or in non-confessional ethics. Recognition also means regulation: the Muslim Executive, the body meant to represent Islam to the state, has been a recurring source of political friction, and successive federal governments have reorganised it or withdrawn confidence in it.

Two Regions, Two Religious Histories

Flanders

Dutch-speaking Flanders was the heartland of Belgian Catholicism. The Catholic party and its successors dominated Flemish politics for over a century, and the Church built a dense network of schools, hospitals, youth movements and farmers' organisations. Even now most Flemish secondary pupils attend schools in the Catholic network, which are state-funded and largely secular in atmosphere but Catholic in governance.

Wallonia

French-speaking Wallonia industrialised early, and its coal and steel valleys produced a powerful socialist movement with a strongly anticlerical streak. Liberal and socialist politics there were built in explicit opposition to clerical influence. The result is that Wallonia secularised earlier and more sharply than Flanders, and organised secular humanism has deeper institutional roots.

Brussels

Officially bilingual and demographically unlike either region, Brussels is where the map gets complicated: a residually Catholic French-speaking population, a large Muslim population, and the highest concentration of Orthodox, evangelical and African-founded congregations in the country.

The Schoolstrijd and the Politics of the Pew

For over a century the central fault line in Belgian politics was not language but religion, and the battleground was schools. The schoolstrijd, or school war, pitted Catholics who wanted state money for church schools against liberals and socialists who wanted a secular public system. It flared in the 1870s and again bitterly in the 1950s, until the School Pact of 1958 defused it by funding both networks - a compromise that still governs Belgian education.

Religion also nearly broke the monarchy. The Royal Question of 1950, over whether Leopold III should return to the throne, split the country almost exactly along confessional and regional lines: Catholic Flanders voted yes, socialist Wallonia voted no, and the king abdicated in favour of his son to prevent open conflict. When language later replaced religion as the defining cleavage it split the Catholic institutions too - most famously in 1968, when Flemish protests forced the ancient Catholic University of Leuven to divide, with the French-speaking half decamping to build an entirely new town at Louvain-la-Neuve.

Why Belgians Stopped Going to Mass

The 1960s did the initial damage here as elsewhere in western Europe: prosperity, mobility, television, the sexual revolution and a generation that stopped taking clerical authority as given. Belgium then added something of its own. From 2010 onwards, revelations about the sexual abuse of children by Belgian clergy landed with exceptional force, including the resignation of the Bishop of Bruges after he admitted abusing a nephew, and police raids on church premises that became a legal scandal in their own right.

The effect was cumulative rather than instant. A widely watched Flemish television documentary in 2023 revisited the abuse record and triggered a fresh surge of formal requests to be struck from baptismal registers, along with a parliamentary inquiry. Belgium had already legalised euthanasia and same-sex marriage over strong episcopal objection, which was itself evidence of how little political weight the hierarchy retained.

Brussels and the Making of a Muslim Minority

Belgium signed bilateral labour agreements with Morocco and Turkey in 1964, recruiting workers for coal mines and heavy industry. Families followed, the industries closed, and the communities stayed - overwhelmingly in Brussels and in industrial cities such as Antwerp, Charleroi and Liege. Today roughly a quarter of the Brussels-Capital Region's residents are Muslim, and Islam is a very large presence in municipalities such as Molenbeek and Schaerbeek.

The Grand Mosque of Brussels sits in the Cinquantenaire Park in a converted nineteenth-century exhibition pavilion, handed to Saudi Arabia on a long lease in the 1960s. The Belgian government revoked that lease in 2018 amid concerns about foreign influence and moved to bring the mosque under Belgian Muslim management. It is a fair illustration of how the recognition system cuts both ways, granting status and asserting control at the same time.

Catholicism as Heritage: Beguinages, Processions and Trappist Beer

What survives most robustly is Catholicism as culture. Thirteen Flemish begijnhoven - walled courtyard settlements built from the thirteenth century for lay religious women who took no permanent vows - were inscribed together on the UNESCO World Heritage list in 1998, and those at Bruges, Leuven and Kortrijk are still lived in. Ghent's Saint Bavo's Cathedral holds the Ghent Altarpiece, completed by the Van Eyck brothers in 1432 and arguably the most stolen artwork in history.

Processions remain genuinely popular events rather than museum pieces. Bruges stages the Procession of the Holy Blood each Ascension Day, recognised by UNESCO as intangible cultural heritage, and Hasselt holds its Virga Jesse procession every seven years. Belgium's six Trappist breweries - Chimay, Orval, Rochefort, Westmalle, Westvleteren and Achel - remain working monastic enterprises, which is why a country that has largely stopped praying still exports its abbeys' beer to the world.