On Halloween, Pope Francis will fly to Sweden to commemorate the 500th anniversary of the Protestant Reformation, together with leaders of the Lutheran World Federation and representatives of other Christian Churches.

The joint ecumenical commemoration of the start of the Reformation will take place in the southern Swedish city of Lund where the Lutheran World Federation was founded in 1947. The one-day event will include a common worship service in Lund cathedral based on a Catholic-Lutheran “Common Prayer” liturgical guide.

The Pope’s visit will underscore the important ecumenical developments that have taken place during the past 50 years of dialogue between Catholics and Lutherans.

Sweden is the least religious nation in the Western world, with nearly 80 percent of the population identifying either as “not religious” or “convinced atheists,” according to the most recent study carried out by polling firm WIN/Gallup International.

The country has been predominantly Lutheran since the Protestant Reformation in the 16th century, and until the year 2000, the Lutheran Church of Sweden was the official state church.

Just this year, Sweden opened its first “atheist cemetery” with a strict policy banning all religious symbols in order to accommodate the nation’s massive nonbelieving population. Although the Church of Sweden is not allowed to express its core beliefs in any way on cemetery property, it will nonetheless manage the upkeep of the graveyard.

While Christian practice in the country is at an all-time low, mosque attendance has been rising steadily thanks to growing numbers of mostly Muslim immigrants arriving in Sweden in recent years. Sweden has been referred to as the “world’s capital of asylum seekers” and some 17 percent of Swedes are now foreign-born.

Sweden’s mass immigration has radically transformed many Swedish cities, leading to the development of Muslim-controlled “no-go zones” where law enforcement fears to enter.

In certain parts of Sweden, police say that up to 25 percent of their time and resources are spent on incidents involving migrants, and last month the Swedish government allocated a further two billion Swedish Krona for policing to 2020.

During his one-day trip to Sweden, Pope Francis will celebrate a public Mass in Malmo, a gateway for thousands of immigrants who have poured into Sweden over the last few years. The Mass will take place at Malmo’s 26,500-seat stadium, which is reportedly nearly sold out.

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