Immediately following the collapse of the Nazi dictatorship at the end of World War II, the need for a new political order in Germany was paramount. Simultaneous yet unrelated meetings began occurring throughout Germany, each with the intention of planning a Christian-democratic party. The CDU was established in Berlin on 26 June 1945 and in Rheinland and Westfalen in September of the same year.
The founding members of the CDU consisted primarily of former members of the Centre Party, the German Democratic Party, the German National People's Party and the German People's Party. Many of these individuals, including CDU-Berlin founder Andreas Hermes, were imprisoned for the involvement in the German Resistance during the Nazi dictatorship. In the Cold War years after World War II up to the 1960s (see Vergangenheitsbewältigung), the CDU also attracted conservative, anti-communist former Nazis and Nazi collaborators into its higher ranks (like Hans Globke and Theodor Oberländer). A prominent anti-Nazi member was theologian Eugen Gerstenmaier, who became Acting Chairman of the Foreign Board (1949-1969).
One of the lessons learned from the failure of the Weimar Republic was that disunity among the democratic parties ultimately allowed for the rise of the Nazi Party. It was therefore crucial to create a unified party of Christian democrats—a Christian Democratic Union. The result of these meetings was the establishment of an interconfessional (Catholic and Protestant alike) party influenced heavily by the political tradition of liberal conservatism. The CDU experienced considerable success gaining support from the time of its creation in Berlin on 26 June 1945 until its first convention on 21 October 1950, at which Chancellor Konrad Adenauer was named the first Chairman of the party.
Adenauer era (1949–1963)
The election poster of 1957 reading "No experiments" and featuring then Chancellor Konrad Adenauer
what would be the only election in which the CDU obtained an absolute majority
In the beginning, it was not clear which party would be favored by the victors of World War II, but by the end of the 1940s the governments of the United States and of Britain began to lean toward the CDU and away from the Social Democratic Party of Germany (SPD). The latter was more nationalist and sought German reunification even at the expense of concessions to the Soviet Union, depicting Adenauer as an instrument of both the Americans and the Vatican. The Western powers appreciated the CDU's moderation, its economic flexibility and its value as an oppositional force to the communists which appealed to European voters at the time. Adenauer was also trusted by the British.
The party was split over issues of rearmament within the Western alliance and German unification as a neutral state. Adenauer staunchly defended his pro-Western position and outmanoeuvred some of his opponents. He also refused to consider the SPD as a party of the coalition until he felt sure that they shared his anti-communist position. The principled rejection of a reunification that would alienate Germany from the Western alliance made it harder to attract Protestant voters to the party as most refugees from the former German territories east of the Oder were of that faith as were the majority of the inhabitants of East Germany.
The CDU was the dominant party for the first two decades following the establishment of West Germany in 1949. Adenauer remained the party's leader until 1963, at which point the former minister of economics Ludwig Erhard replaced him. As the Free Democratic Party (FDP) withdrew from the governing coalition in 1966 due to disagreements over fiscal and economic policy, Erhard was forced to resign. Consequently, a grand coalition with the SPD took over government under CDU Chancellor Kurt Georg Kiesinger.
The SPD quickly gained popularity and succeeded in forming a social-liberal coalition with the FDP following the 1969 federal election, forcing the CDU out of power for the first time in its history. The CDU/CSU were highly critical of Chancellor Willy Brandt's "change through rapprochement" policy towards the Eastern bloc (Ostpolitik) and protested sharply against the 1970 treaties of Moscow and Warsaw that renounced claims to the former eastern territories of Germany and recognised the Oder–Neisse line as Germany's eastern border. The Union parties had close ties with the Heimatvertriebene associations (Germans who fled or were expelled from the eastern territories) who hoped for a return of these territories. Seven Bundestag members, including former vice chancellor Erich Mende, defected from FDP and SPD to the CDU in protest against these treaties, depriving Brandt of his majority and providing a thin majority for the CDU/CSU. In April 1972 the CDU saw its chance to return to power, calling a constructive vote of no confidence. CDU chairman Rainer Barzel was almost certain to become the new Chancellor. But not all parliamentarians voted as expected (it was later revealed that two CDU/CSU deputies had been bribed by the East German Stasi): Brandt won the vote and stayed in office. Thus, the CDU continued its role as opposition for a total of thirteen years. In 1982, the FDP withdrew from the coalition with the SPD and allowed the CDU to regain power.
Kohl era (1982–1998)
CDU Chairman Helmut Kohl became the new Chancellor of West Germany and his CDU/CSU–FDP coalition was confirmed in the 1983 federal election.
East German CDU leader Lothar de Maizière
(left) with West German CDU leader Helmut Kohl, September 1990
After the collapse of the East German government in 1989, Kohl—supported by the governments of the United States and reluctantly by those of France and the United Kingdom—called for German reunification. On 3 October 1990, the government of East Germany was abolished and its territory acceded to the scope of the Basic Law already in place in West Germany. The East German CDU merged with its West German counterpart and elections were held for the reunified country. Public support for the coalition's work in the process of German reunification was reiterated in the 1990 federal election in which the CDU–FDP governing coalition experienced a clear victory. Although Kohl was re-elected, the party began losing much of its popularity because of an economic recession in the former GDR and increased taxes in the west. The CDU was nonetheless able to win the 1994 federal election by a narrow margin due to an economic recovery.
Kohl served as chairman until the party's electoral defeat in 1998, when he was succeeded by Wolfgang Schäuble. Schäuble resigned in early 2000 as a result of a party financing scandal and was replaced by Angela Merkel, who remained the leader of the CDU until 2018. In the 1998 federal election, the CDU polled 28.4% and the CSU 6.7% of the national vote, which was the lowest result for CDU/CSU since 1949 and a red–green coalition under the leadership of Gerhard Schröder took power until 2005. In the 2002 federal election, the CDU and CSU polled slightly higher (29.5% and 9.0%, respectively), but still lacked the majority needed for a CDU–FDP coalition government.
Merkel era (2000–2018)
In 2005, early elections were called after the CDU dealt the governing SPD a major blow, winning more than ten state elections, most of which were landslide victories. The resulting grand coalition between the CDU/CSU and the SPD faced a serious challenge stemming from both parties' demand for the chancellorship. After three weeks of negotiations, the two parties reached a deal whereby CDU received the chancellorship while the SPD retained 8 of the 16 seats in the cabinet and a majority of the most prestigious cabinet posts. The coalition deal was approved by both parties at party conferences on 14 November. Merkel was confirmed as the first female Chancellor of Germany by the majority of delegates (397 to 217) in the newly assembled Bundestag on 22 November. Since her first term in office, from 2005 to 2009, there have been discussions if the CDU was still "sufficiently conservative" or if it was "social-democratising". In March 2009, Merkel answered with the statement "Sometimes I am liberal, sometimes I am conservative, sometimes I am Christian-social—and this is what defines the CDU."
Although the CDU/CSU lost support in the 2009 federal elections, their "desired partner" FDP experienced the best election cycle in their history, thereby enabling a CDU/CSU–FDP coalition. This marked the first change of coalition partner by a Chancellor in German history and the first centre-right coalition government since 1998. CDU candidate Christian Wulff won the 2010 presidential election in the third ballot, while opposition candidate Joachim Gauck (a Protestant pastor and former anti-communist activist in East Germany, who was favoured even by some CDU members) received a number of "faithless" votes from the government camp.
The decisions to suspend conscription (late-2010) and to phase-out nuclear energy (shortly after the Fukushima disaster in 2011) broke with long-term principles of the CDU, moving the party into a more socially liberal direction and alienating some of its more conservative members and voters. At its November 2011 conference, the party proposed a "wage floor", after having expressly rejected minimum wages during the previous years. Psephologist and Merkel advisor Matthias Jung coined the term "asymmetric demobilisation" for the CDU's strategy (practised in the 2009, 2013 and 2017 campaigns) of adopting issues and positions close to its rivals, e.g. regarding social justice (SPD) and ecology (Greens), thus avoiding conflicts that might mobilise their potential supporters. Some of the promises in the CDU's 2013 election platform were seen as "overtaking the SPD on the left". While this strategy has proven to be quite successful in elections, it also raised warnings that the CDU's profile would become "random", the party would lose its "essence" and it might even be dangerous for democracy in general if parties became indistinguishable and voters demobilised.
President Wulff resigned in February 2012 due to allegations of corruption, triggering an early presidential election. This time, the CDU supported, reluctantly, nonpartisan candidate Joachim Gauck. The CDU/CSU–FDP coalition lasted until the 2013 federal election, when FDP lost all their seats in the Bundestag, while the CDU/CSU won their best result since 1990, only a few seats shy of an absolute majority. This was partly due to the CDU's expansion of voter base to all socio-structural groups (class, age or gender), partly due to the personal popularity of Chancellor Merkel. After talks with the Greens had failed, the CDU/CSU formed a new grand coalition with the SPD.
Despite their long-cherished slogan of "There must be no democratically legitimised party to the right of CDU/CSU", the Union has a serious competitor to its right since 2013: The right-wing populist Alternative for Germany (AfD) was founded with the involvement of disgruntled CDU members. It drew on the discontent of some conservatives with the Merkel administration's handling of the European debt crisis (2009–14) and later the 2015 refugee crisis, lamenting a purported loss of sovereignty and control or even "state failure". Nearly 10 percent of early AfD members were defectors from the CDU. In the 2017 election, the CDU/CSU lost a large portion of their voteshare. After failing to negotiate a coalition with the FDP and Greens, they continued their grand coalition with the SPD. In October 2018, Merkel announced that she would step down as leader of the CDU in December 2018, but wanted to remain as Chancellor until 2021. Since the 2017 election, CDU has seen its polling numbers declining even further.
On 7 December 2018, Annegret Kramp-Karrenbauer was elected as new party leader of the CDU in the Christian Democratic Union of Germany leadership election.