No party has led the German government as often as the Christian Democratic Union (CDU), having occupied the chancellor's office for 57 of the 72 years of the Federal Republic of Germany's existence. But, despite that, the CDU is anything but a monolithic or homogeneous political bloc.

Founded in 1945 as an interdenominational Christian party, the CDU effectively succeeded the prewar Catholic Centre Party, and it has never polled lower than the 31% it won at the first vote in postwar Germany in 1949.

If anything, the key to the party's success over the years has been its ability to speak to the political center — and to produce iconic, broadly popular leaders.

The Adenauer era

The CDU began coalescing in the immediate aftermath of World War II while Germany still lay in ruins, and the first party chairman was very much a man of history. Sixty-nine-year-old Konrad Adenauer was a former mayor of Cologne and a member of the Center Party in the Weimar Republic. He had clashed repeatedly with the Nazi regime during the Third Reich and thus had anti-fascist credentials.

Adenauer led the CDU to a 31% plurality in the first-ever election in the Federal Republic in 1949, becoming chancellor by a single vote (in essence, his own) in parliament. But, although Adenauer initially just scraped into power, the party gained in popularity, the four governments he led were very stable, and the CDU came to be seen as the guarantor of German solidity and prosperity. Campaign posters often featured the slogan "No experiments!"

In many respects, Adenauer set a centrist tone that continues today. He was a staunch advocate for West Germany's alignment of itself with the Western Allies, particularly the US. But he also encouraged the country's rapprochement with Western Europe and especially France and remained convinced that the Federal Republic would reunite with Communist East Germany someday — though it was a day he would never see for himself. 

Adenauer's reign came to an end in 1963, and he died four years later at the age of 91.

The Kohl epoch

Together with its Bavarian sister party, the Christian Social Union (CSU), the CDU traditionally commands the most votes in Germany, but the party spent 13 years out of power in the late 1960s and 1970s until lumbering Rhinelander Helmut Kohl recaptured the chancellery in 1982. He hardly swept to power, only becoming chancellor because the Free Democrats (FDP) abandoned their coalition with the SPD and formed a new alliance with his conservatives. 

Kohl wasn't really a government-slashing conservative in the mold of Margaret Thatcher or Ronald Reagan. Initially, he wasn't known for much of anything at all except a stagnant economy and was considered likely to get chucked out of office sooner or later. Then came November 9, 1989.

Kohl's handling of the demise of communism in Eastern Europe and the reunification of Germany continued Adenauer's policy of advancing German national interests while further integrating the country into Western Europe. Thanks to Kohl, whose death in June 2017 was marked by an unprecedented memorial service in the European Parliament in Strasbourg, the CDU will forever be known as the "party of unity."  

Kohl wasn't able to solve the socioeconomic problems accompanying reunification, however, and, after losing the 1998 election, he left the CDU in the midst of a campaign contributions scandal and a new leadership battle. But from that wreckage emerged the CDU's third notable leader.

The Merkel years

Chancellor Angela Merkel hardly stormed into office, reluctantly forming a grand coalition with the Social Democrats (SPD) after a close election in 2005 to gain power. But she grew into the job and consistently ranked as Germany's most well-known, most trusted, and most well-liked politician. If there's one reason why the CDU vastly outperformed the SPD in opinion polls for many years, Merkel was it.

Like Adenauer and Kohl, Merkel was a centrist and a pragmatist. The position for which she may be remembered best is her welcoming stance toward refugees, which caused her to dip temporarily in the polls and hurt her popularity in the party.

Over the past years Merkel's CDU has moved further toward the center than ever before in its history. Abolishing military conscription and phasing out nuclear energy were two of the most radical changes during her tenure.

Many CDU members reject same-sex marriage and abortion, while Merkel — a Protestant pastor's daughter — and others paid lip service to Christian values, turning the CDU into an outwardly secular party, leaving the Catholic-dominated CSU to take up more overtly religious positions.

Ever the pragmatic tactician, Merkel opened the door to legalizing same-sex marriage in 2017  by allowing a conscience vote in the Bundestag and then voted against it herself.

The CDU stands for fiscal stability, but it doesn't advocate the sort of hostility toward the social welfare state that's a feature of conservative movements in other parts of the world. The CDU advocates canceling out the country's debt, favors security and increased state surveillance and is generally more market-friendly than the SPD.

In foreign policy, the CDU is traditionally very positive toward the United States and a strong trans-Atlantic partnership. Critics say the chancellor has always been more interested in smooth governance than ideology, and Merkel herself might very well not disagree with that assessment.

Though Adenauer and Erhard cooperated with non-Nazi parties to their right, the CDU has more recently worked to marginalize its right-wing opposition.

In the last general election, in 2017, the CDU lost over eight percentage points from the 2013 vote, when it polled 41.5%. Analysts found that many voters abandoned Germany's biggest party for the far-right Alternative for Germany (AfD).

Post-Merkel era

When Merkel stepped down from the CDU party leadership, she was succeeded initially by one of her allies: Annegret Kramp-Karrenbauer, who resigned after a dramatic drop in support. She, in turn, was succeeded in January by Armin Laschet , who promised to continue Merkel's course.

But, in view of its poorest showing ever in Bundestag elections, there is growing concern among the CDU/CSU about serious upheavals. "If the CDU/CSU is not in government, the party will face the most difficult times," CSU Chairman Markus Söder told the Welt am Sonntag newspaper ahead of Sunday's vote, which saw the party plummet to 24%.

Wing fights and personal disputes are about to break out openly. Laschet may be forced to resign as CDU leader and the party conservatives may emerge strong. The conservative wing of the party could rally around finance expert and former Blackrock CEO, Friedrich Merz, an old Merkel foe who lost to Laschet in the race for the party leadership.

Many CDU supporters no longer know what their party stands for. Party researcher Oskar Niedermayer told the Tagesspiegel newspaper: "It's quite clear that the CDU is on the verge of losing its status as a big tent party forever." In the European Union, he said, there are enough examples of Christian democratic parties that have collapsed after electoral disasters and never regained their former strength, pointing to the Democrazia Cristiana in Italy as an example.

This is an updated version of a previous article.

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