Why the small town in Türkiye chosen by Pope Leo XIV for his first international trip is so fundamental to Christianity

The Pope, dressed in white, waves to the crowd from his papal car with a gesture of his left hand. Men or children in military uniform take photos in the background. — photo caption, Pope Leo XIV, the spiritual leader of Catholics, took office in May after the death of his predecessor, Pope Francis.

- author, Hilkin Dogac Buran and Esra Yalcinalp
- Author title, BBC Turkish Service
6 hours

At first glance, there’s nothing to suggest that the sleepy Turkish city of Iznik, about a two-hour drive from Istanbul, is an ancient city that changed the course of history.

Exploring this city of 45,000 only takes half an hour on foot, through its picturesque narrow streets with balconies overflowing with roses and ivy.

You can reach the shores of Lake Iznik on the other side without seeing any trace that this was once the capital of the Byzantine and Ottoman Empires.

However, next week, the city formerly known as Nicaea will host Pope Leo XIV, the leader of the Catholic Church, on his first trip abroad since being installed as pope in May.

An aerial view of the Hagia Sophia Orhan Mosque, an ornate brick building with small domes and a single minaret overlooking a small square and surrounded by manicured gardens. The lake can be seen in the background, on the other side of the city. — photo caption, Iznik, a small city 140 km from Istanbul, is a site of great historical importance.

The trip will focus primarily on a ceremony the pope will attend with Greek Orthodox Patriarch Bartholomew and other Christian leaders to commemorate the 1,700th anniversary of the First Council of Nicaea, held in 325 AD. C.

This visit was originally planned by the late Pope Francis, who died last April. The ceremony was postponed after his death.

“One of the deepest wounds in the life of the Church today is the fact that we as Christians are divided,” Pope Leo XIV declared in an interview published in September.

He added that commemorating the Council of Nicaea is important because it constitutes a meeting place for different Christian sects.

Leo XIV will be the fifth pope to visit Türkiye. There are no official statistics on the number of Christians in the country, but the US State Department report for 2023 reached a figure of 150,000, based on reports from the Christian denominations themselves.

The Pope is scheduled to meet with President Recep Tayyip Erdogan in the capital, Ankara, on November 27, before traveling to Iznik on November 28.

But what makes Iznik such an important place for Christians?

A decisive moment

We have to go back to the fourth century, when the First Council of Nicaea was held, to find the answer.

The Roman Empire at that time extended from Scotland to the Red Sea and from Morocco to the deserts of modern-day Syria, Jordan, and Iraq.

At the helm was Constantine I, the first Christian emperor.

It has granted Christians the broadest legal rights since the death of Jesus Christ three centuries ago, allowing them to practice their religion openly.

Emperor Constantine held the council with the aim of uniting the empire and the church. He wanted to meet with the clergy to resolve disagreements about faith. Council in 325 AD. C. It would mark a turning point in Roman and Christian history.

For centuries, the city was as important to Christianity as Jerusalem, Rome, or Constantinople.

A 16th-century fresco in the Sistine Chapel depicting the First Council of Nicaea. In the background are several seated men holding crowns, while in the foreground is a man holding a scepter and crown. The Walls of Nicaea can be seen in the upper left corner. — photo caption, A 16th-century fresco in the Sistine Chapel depicting the First Council of Nicaea.

The clergy initially decided to meet in present-day Ankara, but Emperor Constantine wrote a letter ordering them to go to Nicaea, historian Turhan Kakar of Mugla Sitki Kocman University told the BBC Turkish Service.

Constantine wanted to personally lead the council, according to Kakar: “He knew, from previous church meetings, that the bishops would resist if left to their own devices.”

The historian notes that Constantine I turned religion into a “state instrument” with the Council of Nicaea.

“When the bishops arrived at Nicaea, they represented their own communities; when they returned to their places of origin, they represented the state.”

Basic values of Christianity

Paolo Raphael, rector of St. Stephen’s Catholic Church in Istanbul, agrees that this council was when “the church began to cooperate with the state.”

Father Raphael told BBC News Turkish that the council helped define the basic beliefs of Christianity, adding that in Nicaea a consensus was reached about the nature of Jesus Christ.

It was clearly defined that there is only one God who eternally exists in three divine persons: Father, Son, and Holy Spirit, and a doctrine was written that affirmed the core values of Christianity.

Proving the divinity of Christ was a key moment in the fight against what was known as the “Arian heresy,” which denied that Jesus was God.

Pope Leo

“For Christians, this is the center of our faith,” Raphael says of the Council’s outcome.

An aerial view of part of the floor mosaic, which was first discovered 11 years ago during the construction of a sewer, has been fully revealed following archaeological excavations launched this year in the Iznik district of Bursa, Turkey. — photo caption, Emperor Constantine held the council with the aim of uniting the empire and the church.

Greek Orthodox Metropolitan Maximos Feginopoulos points out that the teachings agreed upon at the council still maintain their importance today.

He adds that Iznik is considered a sacred pilgrimage center for Christians around the world.

The common denominator among all churches

The celebration of the 1,700th anniversary of the Council gives Christians the opportunity to celebrate an important symbol of the universality of the Church.

Professor Kakar points out that when the Council of Nicaea was held, the Christian churches were not yet divided between Catholic and Orthodox, which is why this historical event is considered a “unifying platform” by contemporary spiritual leaders.

Fegenopoulos refers to the First Council of Nicaea as “the common denominator of all Christian churches that express their beliefs today, as in the past.”

He stressed that the Pope’s visit and the memorial ceremony will highlight “the historical and cultural heritage of the region and Turkey.”

Aerial photography of the Iznik site. Partially submerged masonry can be seen defining the ancient walls of the church, and a viewing point extends into the water from an adjacent building. — photo caption, The ruins of the Church of Saint Neophyte were discovered in 2014.

The memorial service will be held in Iznik, near the archaeological site of the Church of Saint Neophytos, located on the banks of the lake.

Bursa University professor Mustafa Sahin, who directs archaeological excavations in Iznik, claims that this building could be the church that theological sources call the “Church of the Holy Fathers,” named after the clergy of the First Council.

He claims that this is one possible place where the council could have met 1,700 years ago.

It is generally believed that the first council was held outside the city walls and next to the lake, but archaeological studies have not yet provided any evidence to support this theory.

Professor Sahin told BBC Turkish that he estimates that the cathedral was built later, at the end of the fourth century, and that it may have been erected on the site where Saint Neophytus is believed to have been killed by the Romans while trying to spread Christianity in the early fourth century.

Sahin also says that it is possible that the council was held in an imperial palace, which has not yet been discovered.

A computer-generated 3D model of a lakeside cathedral, surrounded by trees. The building is made of brick and covered with red clay tiles on the roof. — photo caption, Virtual reconstruction of the Iznik Church based on archaeological remains.

Speaking about the visit, Pope Leo XIV highlighted the importance of Iznik in the past and present:

“Some had initially planned to hold a meeting between me and Patriarch Bartholomew of Constantinople. I requested that this meeting in Iznik be an ecumenical opportunity to invite Christian leaders from different religions or Christian communities.”

“Since Nicene is a faith, it is one of those times when we can all make a common statement of faith before divisions arise.”

On November 29, Pope Leo XIV will celebrate Mass for about 6,000 people before traveling to Lebanon on November 30 for the next leg of his trip.

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