For Pope Francis, the pre-Christmas period is a time of reconciliation. He spent the first Sunday of Advent in Istanbul with the Ecumenical Patriarch Bartholomew, a milestone in the history of relations between the Catholic and the Orthodox church, also using his trip to Turkey to reach out to Muslims. Moreover, the pope is keen to deepen China's ties to the Catholic church. Last week, it emerged that after four years of unofficial talks, Beijing reportedly proposed to review appointments of bishops jointly with the Vatican. This is an important issue for the Catholic church, given its declining numbers: Along with South America and Africa, China represents the most promising opportunity - as yet untapped - for growth.

China's fears of Catholicism

Until now, Beijing has never been particularly well-disposed to Catholics, and has certainly never been willing to let them have any political say. The separation between church and state is a stark one in China, a principle that doesn't only apply to Catholics. Beijing is of the opinion that the Vatican, with the help of Nobel Peace Prizewinner Lech Walesa, played a key role in bringing down the Soviet Union. The former firebrand who led the strikes at the Gdansk dockyards spent the 1980s fighting Poland's communist leadership. On June 4, 1989, the day of Beijing's bloody crackdown on students and protestors on Tiananmen Square, Walesa's Solidarity won Poland's first partly free elections. In late 1990, he won Poland's presidential election.

This goes some way to explaining why it took the Chinese government 25 years to reach a compromise agreement with the Vatican, decades after Mao forced the Catholic church, which was officially recognized in China, to sever diplomatic relations with the Vatican in 1951. Ever since then, the Chinese Patriotic Catholic Association, which toes the Communist party line, has named Catholic bishops in mainland China without the Vatican's approval. As far as the government was concerned, the section of China's Roman Catholic community which was unwilling to sever ties with the pope splintered off into an illegal, underground church.

The underground Catholic movement

Because the underground movement's bishops are appointed by the pope, Beijing does not recognize their legitimacy. Even today, members of the Chinese Roman Catholic house churches, as they are known, face persecution and oppression, and most services are held in secret. Only 15 million of China's population of 1.3 billion belong to either the government-sanctioned Catholic church or the "underground" churches loyal to the Vatican. Theoretically, there could be many more.

A growing number of people are now turning to faith in response to China's economic upswing, and Beijing is taking a conciliatory approach. It seems that the government would rather see people embracing Catholicism than falling victim to any of China's religious sects. After a noticeable rapprochement between the two Catholic camps in recent months, it was announced last week that China has proposed a joint system for appointment of bishops. In this respect, the Chinese Catholic church is acting much like a major car company: Anyone looking to expand in China has little choice but to agree to a joint venture with the state.

The terms of the deal

But before the Roman-Catholic church can enjoy official and legal status in mainland China, Beijing insists that the Vatican must sever diplomatic ties with Taiwan. The Holy See is the sole European state, and indeed one of only a few worldwide, to recognize the Republic of China - Taiwan - as an independent state.

That's no great surprise, given how well-established the Roman-Catholic church is there. Like most states, the Vatican is pragmatic. The Pope is more interested in the new followers he could find in China than the current ones he has in Taiwan. Rome has already offered to move the embassy from Taiwan to Beijing.

But it's possible that Pope Francis is drawn to China for completely different reasons. He is, after all, the first pope to belong to a Jesuit order - the very same order that introduced Roman-Catholicism to China 500 years ago. Beijing has yet to invite the pope for a visit, even though he has publically expressed his interest. But at least Beijing allowed Francis to become the first pontiff ever to fly through Chinese airspace, on his way to South Korea.

One of Germany's leading experts on China, Frank Sieren has lived in Beijing for20 years.