Germany–Holy See relations
Formal diplomatic relations between the Holy See and the current Federal Republic of Germany date to the 1951 and the end of the Allied occupation. Historically the Vatican has carried out foreign relations through nuncios, beginning with the Apostolic Nuncio to Cologne and the Apostolic Nuncio to Austria. Following the dissolution of the Holy Roman Empire and the Congress of Vienna, an Apostolic Nuncio to Bavaria replaced that of Cologne and that mission remained in Munich through several governments. From 1920 the Bavarian mission existed alongside the Apostolic Nuncio to Germany in Berlin, with which it was merged in 1934.
Recently, German Chancellor Angela Merkel, in her nine page address at the Bavarian Catholic Academy's conference on "Political Action based on Christian Responsibility," noted that Benedict XVI's new encyclical Caritas in Veritate points to the way forward in the current economic crisis.
She was particularly impressed by the passage that read: "The primary capital to be safeguarded and valued is man, the human person in his or her integrity." 
As soon as 496, Frankish King Clovis I was baptized together with many members of his household. In contrast to the eastern German tribes, who became Arian Christians, he became a Catholic. Following the example of their king, many Franks were baptized too, but their Catholicism was mixed with pagan rites.
The investiture controversy was the most significant conflict between Church and state in medieval Europe. In the 11th and 12th centuries, a series of popes challenged the authority of European monarchies over control of appointments, or investitures, of church officials such as bishops and abbots.
On September 25, 1555, Charles V, Holy Roman Emperor and the forces of the Schmalkaldic League signed the Peace of Augsburg to officially end the religious wars between the Catholics and the Protestants. This treaty made legalized the partitioning of the Holy Roman Empire into Catholic and Protestant territories.
Under the treaty, the religion of the ruler (either Lutheranism or Catholicism) determined the religion of his subjects. This policy is widely referred to by the Latin phrase, cuius regio, eius religio ("whose reign, his religion", or "in the prince's land, the prince's religion"). Families were given a period in which they were free to emigrate to regions where their desired religion prevailed.
Post-French revolution era
In the war of the First Coalition, revolutionary France defeated the coalition of Prussia, Austria, Spain, and Britain. One result was the cession of the Rhineland to France by the Treaty of Basel in 1795.
Eight years later, in 1803, to compensate the princes of the annexed territories, a set of mediatisations was carried out, which brought about a major redistribution of territorial sovereignty within the Empire. 
In the mid-19th century, the Catholic Church was also seen as a political power, even in Protestant Prussia, exerting a strong influence on a fourth of the people. However, from the Catholics' point of view (especially where Catholics were the majority as in the Rhine Province and its Saar area, Alsace and Lorraine, and Silesia), Catholics often felt intimidated by self-consciously Protestant rulers.
The religious make-up at the time was two-thirds Protestant and one third Catholic. Prussia, for example, had a Protestant dynasty, a Protestant state church, and power Junker class and an officer corps with high social status and almost no Catholic members. (Those members of the German Catholic aristocracy who chose a military career, for example, often preferred the Austrian army.)
In 1871–1878, Chancellor Bismarck, who controlled both the German Empire and the Kingdom of Prussia, launched the "Kulturkampf" in Prussia to reduce the power of the Catholic Church in public affairs, and keep the Polish Catholics under control. German nationalists feared the Polonization of the Prussian East. Thousands of priests and bishops were harassed or imprisoned, with large fines and closures of Catholic churches and schools. While the pope did control the selection of bishops, the Catholics supported unification and most of Bismarck's policies, and were angry at his systematic attacks.
Bismarck sought to appeal to anticlerical liberals and Protestants but he failed because the Catholics were unanimous in their resistance and organized themselves to fight back politically, using their strength in other states besides Prussia. (The Kulturkampf did not extend to the other German states such as heavily Catholic Bavaria.) Bismarck saw the Kulturkampf as a means of stopping this trend, which was led by the Catholic clergy in West Prussia, Poznania and Silesia. The Poles were Catholics and subjected to harassment in the fields of education, occupations, business and public administration. German was declared to be the only official language, but in practice the Poles only adhered more closely to their traditions.
There was little or no violence, but the new Roman Catholic Center Party won a quarter of the seats in the Reichstag (Imperial Parliament), and its middle position on most issues allowed it to play a decisive role in the formation of majorities. The culture war gave secularists and socialists an opportunity to attack all religions, an outcome that distressed the Protestants, including Bismarck, who was a devout pietistic Protestant. The Catholic anti-liberalism was led by Pope Pius IX; his death in 1878 allowed Bismarck to open negotiations with Pope Leo XIII, and led to his abandonment of the Kulturkampf in stages in the early 1880s.
After it failed to seize control of the Bavarian state in 1923, the nascent Nazi Party, by that time sharing the Bavarian bishops' view about the incompatibility of National Socialism and Christianity, no longer wanted to court Catholics.
Hitler wanted to broaden its base. The Party leadership became anti-Catholic (especially attacking the bishops) and its inherent anti-Semitism became more virulent. To counter this, the bishops adopted a conditional ban or prohibition in regard to Catholic membership in the Party, which later (as Nazism spread throughout Germany) varied from diocese to diocese.
Pius XI was eager to negotiate concordats with any country that was willing to do so, thinking that written treaties were the best way to protect the Church's rights against governments increasingly inclined to interfere in such matters. Twelve concordats were signed during his reign with various types of governments, including some German state governments. When Hitler became Chancellor of Germany in January 1933 and asked for a concordat, Pius XI accepted. Negotiations were conducted on his behalf by Cardinal Eugenio Pacelli, who later became Pope Pius XII (1939–1958). The Reichskonkordat was signed by Pacelli and by the German government in June 1933, and included guarantees of liberty for the Church, independence for Catholic organisations and youth groups, and religious teaching in schools. The German bishops wanted the concordat, and its swift passage gave the new Nazi regime a considerable degree of legitimacy for its good behaving in foreign policy despite its long history of violent rhetoric. Kent says, "Without a doubt, the concordat was a diplomatic victory for Hitler. It was his first major success in the field of foreign policy, and it indicated to the world that the German Chancellor was politically reliable and trustworthy." Within a few weeks, however, serious friction arose over Nazi threats to the status of the Church. In particular there were issues of the oppression of Catholics of Jewish descent, dismissal of Catholics from the civil service, freedom of expression for Catholic newspapers, pressure on Catholic schools and organizations, sterilization laws, and persecution of nuns and priests.
Mit brennender Sorge
Pius XI responded to ever increasing Nazi hostility to Christianity by issuing in 1937 the encyclical Mit brennender Sorge condemning the Nazi ideology of racism and totalitarianism and Nazi violations of the concordat. The encyclical, written in German, was addressed to German bishops and was read in all parishes of Germany. The encyclical, was kept secret in an attempt to ensure the unhindered public reading of its contents in all the Catholic Churches of Germany. This encyclical condemned particularly the paganism of National Socialist ideology, the myth of race and blood, and fallacies in the Nazi conception of God.
"Whoever exalts race, or the people, or the State, or a particular form of State, or the depositories of power, or any other fundamental value of the human community – however necessary and honorable be their function in worldly things – whoever raises these notions above their standard value and divinizes them to an idolatrous level, distorts and perverts an order of the world planned and created by God; he is far from the true faith in God and from the concept of life which that faith upholds."
After the encyclical German-Vatican relations deteriorated rapidly, and were marked by violent Nazi street demonstrations against two German bishops. Pius XI continued to criticize Nazi policies sharply and publicly, but he also avoided a complete rupture. He died at the peak of tension, in February 1939.
Adler however has examined the transcripts of broadcasts over the Vatican Radio, which reached a wide audience over short wave. He argues that it exposed Nazi persecution of the Church and opposed collaboration with Nazism. It appealed to Catholics to remain true to their faith's injunctions: to defend the sanctity of life and the unity of humankind. In so doing the Pope pursued a policy of spiritual resistance to Nazi ideology and racism.
After World War II, the Catholics in the zone occupied by the Soviet army found themselves under a militantly atheist government. Many parishes were cut off from their dioceses in the western part of Germany. The Soviet zone eventually declared itself a sovereign nation, the German Democratic Republic (GDR). The GDR's constitution proclaimed the freedom of religious belief, but in reality the new state tried to abolish religion.
The Catholic Church was small in East German (most people were Protestants). It had a fully functioning episcopal hierarchy that was in full accord with the Vatican. During the early postwar years, tensions were high. The Catholic Church as a whole and particularly the bishops were resistant to both the regime and Marxist ideology, and the state allowed the bishops to lodge protests, which they did on issues such as abortion. The bishops were, however, closely observed by the Stasi.
After 1945, the Church did fairly well in integrating Catholic exiles from lands to the east (which were given to Poland) and adjusting its institutional structures against the threats of an atheistic state. Within the Church, this meant an increasingly hierarchical structure, whereas in the area of religious education, press, and youth organisations, a system of temporary staff was developed, one that took into account the special situation of the Caritas, a charity organisation. They were hardly affected by Communist attempts to force them into line. By 1950, therefore, there existed a Catholic subsociety that was well adjusted to prevailing specific conditions and capable of maintaining Catholic identity.
With a generational change in the episcopacy taking place in the early 1980s, the state hoped for better relations with the new bishops, but the new bishops instead showed increasing independence from the state by holding unauthorised mass meetings, promoting international ties in discussions with theologians abroad, and hosting ecumenical conferences. The new bishops became less politically oriented and more involved in pastoral care and attention to spiritual concerns. The government responded by limiting international contacts for bishops.
- Christa Pongratz-Lippitt, "Merkel: encyclical is the answer to crisis," The Tablet 1 August 2009, 32.
- Kurt Hoppstädter and HansWalter Herrmann (Publishers, Geschichtliche Landeskunde des Saarlandes, Book 2: Von der fränkischen Landnahme bis zum Ausbruch der französischen Revolution. Selbstverlag des Historischen Vereins für die Saargegend e. V., Saarbrücken 1977, Pg 17/18
- David Blackbourn, Marpingen: Apparitions of the Virgin Mary in Nineteenth-Century Germany (New York: Alfred Knopf, 1994), 29.
- Jonathan Sperber, Popular Catholicism in Nineteenth-Century Germany (Princeton, NJ: Princeton, 1984)
- James Carroll, Constantine's Sword (Houghton Mifflin, 2001), 486.
- Rebecca Ayako Bennette, Fighting for the Soul of Germany: The Catholic Struggle for Inclusion after Unification (Harvard U.P. 2012)
- Blanke, Richard (1981). Prussian Poland in the German Empire (1871–1900).
- Blackbourn, David (Dec 1975). "The Political Alignment of the Centre Party in Wilhelmine Germany: A Study of the Party's Emergence in Nineteenth-Century Württemberg". Historical Journal 18 (4): 821–850. doi:10.1017/s0018246x00008906.
- Clark, Christopher (2006). Iron Kingdom: The Rise and Downfall of Prussia, 1600–1947. pp. 568–576.
- Kevin P. Spicer (2004). Resisting the Third Reich: The Catholic Clergy in Hitler's Berlin. Northern Illinois U.P. p. 10.
- Spicer, Resisting, 10
- Latourette, Christianity in a Revolutionary Age: A History of Christianity in the 19th and 20th Century: Vol 4 The 20th Century in Europe (1961) pp 176-88
- George O. Kent, "Pope Pius XII and Germany: Some Aspects of German-Vatican Relations, 1933-1943," American Historical Review (1964) p 60
- Kent, "Pope Pius XII and Germany: Some Aspects of German-Vatican Relations, 1933-1943," American Historical Review (1964) pp 61-62
- David Cymet (2010). History Vs. Apologetics: The Holocaust, the Third Reich, and the Catholic Church. Lexington Books. pp. 98–99.
- William M. Harrigan, Pius XI and Nazi Germany, 1937-1939," Catholic Historical Review (1966) 51#4 PP 457-486.
- Frank J. Coppa, Pope Pius XII: From the Diplomacy of Impartiality to the Silence of the Holocaust," Journal of Church and State (2013) 55#2 pp 286-306.
- Jacques Adler, "The 'Sin of Omission'? Radio Vatican and the anti-Nazi Struggle, 1940–1942," Australian Journal of Politics & History (2004) 50#3 pp 396-406.
- Stephen R. Bowers, "Private Institutions in Service to the State: The German Democratic Republic'S Church in Socialism," East European Quarterly (1982) 16#1 pp 73–86
- Bernd Schaefer (2010). The East German State and the Catholic Church, 1945-1989. Berghahn Books. ch 1
- Adrian Webb (2008). Routledge Companion to Central and Eastern Europe since 1919. Taylor & Francis. p. 185.
- Bennett, Rebecca Ayako. Fighting for the Soul of Germany: The Catholic Struggle for Inclusion after Unification (2012) excerpt and text search
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- Gross, Michael B. The War against Catholicism: Liberalism and the Anti-Catholic Imagination in Nineteenth-Century Germany (2005) excerpt and text search
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- Latourette, Kenneth Scott. Christianity in a Revolutionary Age: A History of Christianity in the 19th and 20th Century: Vol 1 The Nineteenth Century in Europe (1958) pp 433–42
- Latourette, Kenneth Scott. Christianity in a Revolutionary Age: A History of Christianity in the 19th and 20th Century: Vol 4 The 20th Century in Europe (1961) pp 176–88
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