Athens, Greece - More than a century ago, France passed a landmark law declaring a clean break between church and state. Riots erupted and a papal encyclical denounced the 1905 act as a "most pernicious error."
Such extreme passions long ago cooled. But the core questions remain as strong as ever. Debates over religion, politics and civic life — and how much they should overlap and interact — are demanding attention across Europe in ways more pressing than at any time in recent decades.
It's no longer just about whether to untangle or preserve the old relationships between the secular and spiritual — often only symbolic these days, but still an important stream of revenue for churches.
New fronts are emerging: Traditionalist groups seeking a closer embrace of Europe's Christian heritage, and others predicting that efforts to better integrate Muslim communities will also require new models for the role of religion in public life.
"Religion — for good and bad — is reasserting itself as a force in Europe," said Gerhard Robbers, a professor of political and religious studies at Germany's University of Trier. "The period of secularism is coming to an end. A new landscape is emerging."
But many would argue it's a very uneven terrain.
The European Union's center of gravity is no longer solidly in northern Europe, where church attendance and religious influence are in freefall.
When the EU expanded in 2004, it inherited a swath of Eastern Europe where churches — particularly the Roman Catholic and Christian Orthodox — have been reasserting their voices in civil affairs after being sidelined for decades by communism. Two of the other newcomers have deep church-state bonds: Malta with Catholicism and the Greek-speaking zone of divided Cyprus with the Orthodox church. Two more predominantly Orthodox nations, Bulgaria and Romania, will enter the EU fold in January.
In Poland, another new EU member, top government officials have been guests on a popular Catholic radio station, Radio Maryja, whose ultraconservative views and commentary on political affairs and relations with Jews has drawn criticism from the Vatican.
Many of the new EU states were among the strongest voices in the unsuccessful effort to add a mention of God or Christianity in the EU constitution, which was effectively mothballed after rejection last year by voters in France and the Netherlands. The EU hopes to restart the ratification process, with some officials setting a target of 2008.
German Chancellor Angela Merkel said this year that "Christianity has formed Europe in a decisive way" and should be reflected in an eventual constitution.
In a joint declaration last month in mostly Muslim Turkey, Pope Benedict XVI and the spiritual leader of the world's more then 250 Orthodox, Ecumenical Patriarch Bartholomew, stressed the need to "preserve Christian roots" in European culture while remaining "open to other religions and their cultural contributions."
Such messages resonate with some rightist political groups, such as Austria's Freedom Party or the British National Party, which increasingly see pro-Christian platforms as a way to tap into public anxiety over growing Islamic communities and Turkey's bid for EU membership.
"The crisis that splits Europe is of a cultural order. Its Christian identity is being diluted," said a statement from high-level Roman Catholic and Orthodox envoys following a three-day meeting in Vienna, Austria, in May.
But the general trends appear to be moving in a different direction. There's clear momentum to dismantle or dilute the few remaining "official" church-state links.
In Greece, the head of the powerful Greek Orthodox Church, Archbishop Christodoulos, said he would not object to a "velvet separation" between church and state, which would allow the church to retain its tax breaks and other privileges but would eliminate clergy from presiding at official events such as the swearing-in of political leaders.
A poll in January by the Institute for Greek Public Opinion found nearly 60 percent support for ending the official status of the Greek Orthodox Church.
Anglican clergy in Britain — where the crown is the nominal head of the Church of England — have been steadily dropping the practice of including prayers for the monarch in another small but noticeable crack in the church-state structure, which could come under further strains if Prince Charles takes the throne because of disputes over his divorce and remarriage.
Norway, which is not an EU member but has close economic ties with the bloc, opened hearings in April on whether to separate church and state after 469 years of Lutheranism as its official religion. A government panel recommended the split in January, but it could not happen until at least 2014 because of rules on changing the constitution. Neighboring Sweden ended its "official" Lutheran church in 2000.
"We are witnessing post-Christian Europe taking shape," said Jonathan Bartley, co-director of Ekklesia, a London-based group that examines religious and social trends. "The remaining alliances of religion and governments don't make sense anymore, in many people's eyes, and they are coming apart."
What may emerge in coming decades, experts say, is a greater presence of religious-oriented groups seeking to shape public policies as Europe becomes more culturally and religiously diverse.
"Whatever the form, such dialogue might be able to generate new insights and policy proposals which cut through the antagonisms in the international debate," German theologian the Rev. Konrad Raiser told a World Council of Churches gathering Monday in Geneva. "We live in a divided world and the churches share in this division."