VATICAN CITY – When a pope last visited Turkey — Benedict XVI in 2006 — Muslim-Catholic tensions were so high that the Vatican added a stop at Istanbul's famed Blue Mosque at the last minute in hopes of showing Benedict's respect for Islam.
Pope Francis travels to Turkey this weekend amid new Muslim-Christian tensions and war next door, with Islamic State militants seizing chunks of Iraq and Syria and sending 1.6 million refugees across the border into Turkey.
Francis is expected to tread lightly during his three-day visit, sensitive to the delicate diplomatic tensions at play between Turkey and the international coalition fighting the Islamic State.
But Vatican officials say he will not shy from denouncing violence in God's name and voicing concern for Christians being targeted by the extremists. Remarkably, though, Francis will not meet with any groups of refugees as he has done on previous trips to the region, a clear sign of the Vatican's unwillingness to wade too deeply into the conflict.
Here are five things to look for during Francis' visit, which begins Friday.
TO PRAY OR NOT TO PRAY
When Pope Paul VI made the first-ever papal visit to Turkey in 1967, he fell to his knees in prayer inside Haghia Sophia, the 1,500-year-old site in Istanbul that was originally a Byzantine church and was turned into a mosque after the Muslim conquest of Istanbul — then known as Constantinople — in 1453. The Turks were not pleased. They staged protests, claiming Paul had violated the secular nature of the domed complex, which is now a museum.
Asked if Francis would pray when he visits the massive complex on Saturday, the Vatican was noncommittal. "We'll see what he does," spokesman the Rev. Federico Lombardi said. "If while there the pope personally experiences a moment of spiritual meditation, we'll have to see."
Some Islamic groups in Turkey want Haghia Sophia to be converted back into a mosque, and they have prayed outside the complex on the anniversary of the conquest of Istanbul to push their demand. The government says it has no plans to change Haghia Sophia's status.
AND THE BLUE MOSQUE?
Benedict became only the second pope to step foot in a Muslim house of worship when in November, 2006 he visited the 17th century Sultan Ahmet Mosque in Istanbul, Turkey's most important.
There, he took off his shoes, bowed his head and closed his eyes for nearly a minute in prayer alongside an Islamic cleric in a dramatic gesture of outreach to Muslims.
The mosque visit was added late to Benedict's schedule in a bid to soothe Muslim anger over his now-infamous speech in Regensburg, Germany linking violence to the teachings of the Prophet Muhammad.
Asked if Francis would pray in the mosque as Benedict did, Lombardi took pains to stress the difference between a formal, ritualistic prayer that a Catholic might recite in church and a respectful "spiritual meditation" in a place of worship of another faith.
Turkey's ambassador to the Holy See, Mehmet Pacaci, said the tensions that overshadowed Benedict's visit are "mostly a forgotten issue."
Yet there are some fresh issues with Francis. In September, the head of the government-run Religious Affairs Directorate and Turkey's top cleric called on Francis to take action to stem attacks on mosques in Europe, saying that as many as 70 Muslim places of worship were attacked in Germany this year, compared to 36 last year.
"This can't happen through acts such as washing a young girl's feet or arranging inter-religious football matches and tournaments," Mehmet Gormez said, referring to two of Francis' interfaith initiatives.
The two men meet on Friday in private.
Francis also provoked Turkish anxiety when in June 2013 he told a visiting delegation of Armenian Chrisitans that the massacre of Armenians in Turkey last century was "the first genocide of the 20th century."
The former Cardinal Jorge Mario Bergoglio was particularly close to the Armenian community of Buenos Aires, such that his successor as archbishop recently announced that Francis would celebrate a Mass on April 12, 2015 in St. Peter's Basilica to commemorate the centenary of the start of the massacre.
Historians estimate that up to 1.5 million Armenians were killed by Ottoman Turks around the time of World War I, an event widely viewed by scholars as the first genocide of the 20th century. Several European countries recognize the massacres as such.
Turkey, however, denies that the deaths constituted genocide, saying the toll has been inflated and that those killed were victims of civil war and unrest.
Lombardi, the Vatican spokesman, said the pope's genocide remarks were "in no way a formal or public declaration" and therefore didn't constitute a public assertion that genocide took place.
Francis will be walking straight into another controversy when he visits Turkish President Recep Tayyip Erdogan's huge new palace on once-protected farm land and forest in Ankara, becoming the first foreign dignitary to be hosted at the lavish, 1,000-room complex.
The palace, which dwarfs the White House and other European government palaces, was built at a cost of $620 million. It has drawn the ire of opposition parties, environmentalists, human rights activists and architects who say the construction is too extravagant, destroyed important forest land and went ahead despite a court injunction against it.
Erdogan brazenly dismissed the court ruling saying: "Let them knock it down if they have the power."
The Ankara branch of the Turkish Chamber of Architects sent a letter to the pope this month, urging him not to attend the welcoming ceremony on Friday at the "illegal" palace.
Lombardi brushed off the request, saying Francis was invited to visit by the Turkish government and will go where the Turkish government wishes to receive him.
Technically speaking, the real reason for the visit is for Francis to visit the spiritual leader of the world's Orthodox Christians, Patriarch Bartholomew I.
The two major branches of Christianity represented by Bartholomew and Francis split in 1054 over differences in opinion on the power of the papacy, and the two spiritual heads will participate in an ecumenical liturgy and sign a joint declaration in the ongoing attempt to bridge the divide and reunite the churches.
Ties are already warm: Bartholomew became the first ecumenical patriarch to attend a papal installation since the schism when Francis took over as pope in March 2013. The two have met since on several occasions, including during a visit in Jerusalem in May to commemorate the 50th anniversary of the landmark encounter there of Pope Paul VI and Bartholomew's predecessor, Patriarch Athenagoras.
Fraser reported from Ankara, Turkey.
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