Five centuries after the Reformation triggered a series of long and bloody religious wars across Europe, modern-day Protestants and Catholics believe they have more in common theologically than they do differences, and most would be willing to accept each other as neighbours and family members.

“Theological differences that split western Christianity in the 1500s have diminished to a degree that might have shocked Christians in past centuries,” says a report by the Washington-based Pew Research Center.

The study does note a geographical divide in western Europe, with predominantly Protestant countries in the north and Catholic countries mainly in the south.

The Reformation’s fuse was lit when Martin Luther, a German monk, nailed his 95 theses to the door of a church in Wittenberg on 31 October 1517. The document, written in Latin, fundamentally challenged the authority of the Roman Catholic church.



Luther’s move was part of a backlash against increasing corruption and in particular the highly profitable sale of indulgences, promoted as fast-track tickets to heaven. Luther declared that when it came to “justification” – avoiding hell, and gaining admission to heaven – salvation was a matter between an individual and God.



Swiftly translated into German and other European languages, Luther’s ideas spread across the continent within weeks, triggering religious, political, intellectual and cultural upheaval.



In recent decades there has been a slow rapprochement between the Catholic and Protestant traditions, with greater cooperation and dialogue, encouraged by Pope Francis, although there are still pockets of sectarianism. Last year, leaders of the Catholic and main Protestant churches in Germany issued a joint text calling for a “healing of memories” of past divisions.



Pope Francis has encouraged greater cooperation and dialogue with churches. Photograph: Giuseppe C/PacificPress/Barcroft

Protestants are the majority in five western European countries and Catholics are the biggest group in nine, with a broadly north-south divide, according to the Pew study. Luther’s home country, Germany, is still predominantly Catholic, with a 42% share of the population, compared with 28% Protestant and 24% unaffiliated.

The UK breakdown is 54% Protestant, 17% Catholic and 24% unaffiliated, while Ireland is 75% Catholic, 5% Protestant and 14% unaffiliated. Finland is the most Protestant country, with 73% of the population, and is recorded as having 0% Catholics. Italy is the most Catholic country, at 78%, and is 1% Protestant.



Only in the Netherlands do the unaffiliated make up the largest group, with 48% of the population, compared with 20% Catholic and 18% Protestant.



In all the countries, only small proportions of Catholics and Protestants pray daily, attend services weekly or say religion is very important in their lives.



Across the board, 58% of Protestants and 50% of Catholics in western Europe say the two traditions are religiously more similar than different. But 26% and 34% respectively say the differences outweigh the similarities.

Roughly nine out of 10 or more Protestants and Catholics say they are willing to accept members of the other tradition as neighbours. Large majorities of both groups say they would be willing to accept each other into their families.



Germany is the most tolerant country, with 98% of Protestants and 97% of Catholics willing to accept the other into their families. Portugal and Spain are the least tolerant, with less than 80% of their predominantly Catholic populations willing to accept Protestants as family members.



Pew also records a reconciliation between the two traditions on a key theological issue: whether eternal salvation is attained solely through faith, as Luther believed, or through a combination of faith and good works.



In every country bar one, majorities or pluralities of Catholics and Protestants say both faith and good works are needed for salvation. The exception is Norway, where 51% of Protestants say salvation comes through faith alone.



• This article was amended on 5 September 2017. An earlier version said research by the Pew Research Center showed 48% of people in Germany were Catholic. This has been corrected to 42%.

