Lutheranism
On 15–19 November 1980, John Paul II visited the Federal Republic of Germany on his first trip to a country with a large Lutheran population. In Mainz he met with leaders of the Lutheran and other Protestant Churches, and with representatives of other Christian denominations.
On 11 December 1983, John Paul II participated in an ecumenical service in the Evangelical Lutheran Church in Rome, the first papal visit ever to a Lutheran church. The visit took place 500 years after the birth of Martin Luther, the German Augustinian monk who initiated the Lutheran reformation.
In his apostolic pilgrimage to Norway, Iceland, Finland, Denmark and Sweden of June 1989, John Paul II became the first pope to visit countries with Lutheran majorities. In addition to celebrating Mass with Catholic believers, he participated in ecumenical services at places that had been Catholic shrines before the 16th century Lutheran reformation: Nidaros Cathedral in Norway; near St. Olav's Church at Thingvellir in Iceland; Turku Cathedral in Finland; Roskilde Cathedral in Denmark; and Uppsala Cathedral in Sweden.
On 31 October 1999, (the 482nd anniversary of Reformation Day, Martin Luther's posting of the 95 Theses), representatives of the Vatican and the Lutheran World Federation (LWF) signed a Joint Declaration on the Doctrine of Justification, as a gesture of unity. The signing was a fruit of a theological dialogue that had been going on between the LWF and the Vatican since 1965.
Read more about this topic: Solidarity (Catholic Theology), Relations With Other Faiths