The Christian Democratic Union of Germany (CDU; Christlich Demokratische Union Deutschlands) is the largest political party in Germany. A centre right Christian democratic party, the CDU is a member of the European People's Party (EPP) and the International Democrat Union (IDU).
The CDU does not operate in Bavaria; its role is played by the Christian Social Union (CSU). The CDU cooperates with the CSU at the federal level; although each party maintains its own structure, the two form a common parliamentary group in the German Parliament and do not run opposing campaigns. Their combination is generally referred to as The Union.
CDU was founded after World War II with many members of the former Centre Party, but with the goal to include not only Catholics, but also Protestants, in a common confessional, liberal and conservative party. One of the lessons learned from the failure of the Weimar Republic was that the disunity of the democratic parties was one major reason for the rise of the Nazi Party. So people (partly from the German Resistance) founded a new party without predecessor and called it a "Union" (the term "Union" does not refer to trade unions, which are called "Gewerkschaften" in the German language). The first CDU-leader in Berlin, Andreas Hermes was involved in the July 20 plot and was arrested by Nazi Germany as well als CDUs first leader and West Germany’s first chancellor Konrad Adenauer a former member of Centre Party. Other CDU representatives came from the DDP, the DNVP and DVP.
The CDU was the dominant party with Konrad Adenauer as its leader from 1949 to 1963. Then in 1963, Ludwig Erhard of the CDU succeeded Adenauer, preceding a recession in 1966. This caused the CDU to wane in power and consequently form a coalition with the SPD. Kurt Georg Kiesinger (CDU) then took power as chancellor of West Germany.
However, the SPD turned and formed a coalition with the FDP in 1969, and the CDU thus lost its leadership position for the next 13 years. It was during this time that the CDU developed new conservative economic and foreign policies. The FDP in turn developed a new coalition with the CDU in 1982 after a fall out with the SPD. By 1983, the CDU was back in power with Helmut Kohl as the new Chancellor for West Germany. The CDU was then revived in 1989 when the Berlin Wall fell and the CDU regained popularity.
It was after the people of the GDR peacefully rebelled against their government that West Germany’s chancellor Kohl, with the strong support of the United States, called for the reunification of Germany. On October 3, 1990, the German Democratic Republic was abolished and its territory reannexed to Germany. The East German CDU also merged with its West German counterpart. The same year elections were held for the reunified country. Although Chancellor Kohl was reelected, the party lost much of its popularity because of an economic recession in the former GDR and a tax increase in the west. He was, however, victorious again in the 1994 election.
Helmut 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. In the 1998 general election, the CDU polled 28.4% and the CSU 6.7% of the national vote. In 2002, CDU reached 29.5% and the CSU 9.0%. In 2005 early elections were called after the CDU dealt the governing SPD a major blow, winning more than ten state elections, mostly with a landslide victory. A Grand Coalition between the CDU/CSU and SPD faced the challenge that both parties demanded the chancellorship. However, after three weeks of negotiations, the two parties reached a deal whereby Merkel would become Chancellor and the SPD would hold 8 of the 16 seats in the cabinet and receive a majority of the most prestigious cabinet posts. The coalition deal was approved by both parties at party conferences on November 14. Merkel was elected Chancellor by the majority of delegates (397 to 217) in the newly assembled Bundestag on 22 November.
Opponents of the CDU are the social democratic SPD, the post-communist Left Party/PDS and the left-wing environmentalist Bündnis'90/Die Grünen. The liberal FDP party is considered to be the natural partner of any CDU government (although this was different in the past, when the CDU was more markedly conservative and the FDP more markedly liberal).
25.4 % of members are female and 74.6 % male. The female proportion is higher in the new East Germany states with 29.2 % compared to the former states in West Germany with 24.8 %.
Before 1966 membership totals in CDU organization were only estimated. The numbers after 1966 are based on the total from December 31 of the previous year.
| State group | Chairman | Members | |
| CDU state party group of Baden-Württemberg | Günther Oettinger | 79,000 | |
| Berlin | Ingo Schmitt | 13,000 | |
| Brandenburg | Ulrich Junghanns | 7,000 | |
| Bremen | Bernd Neumann | 3,340 | |
| Hamburg | Michael Freytag | 9,920 | |
| Hessen | Roland Koch | 48,950 | |
| Mecklenburg-Vorpommern | Jürgen Seidel | 7,000 | |
| Lower Saxony | David McAllister (politician) | 55,752 | |
| North Rhine-Westphalia | Jürgen Rüttgers | 185,000 | |
| Rhineland-Palatinate | Christian Baldauf | 51.187 | |
| Oldenburg | Manfred Carstens | 13,600 | |
| Saarland | Peter Müller | 22,000 | |
| Saxony | Stanislaw Tillich | 15,000 | |
| Saxony-Anhalt | Thomas Webel | 9,000 | |
| Schleswig-Holstein | Peter Harry Carstensen | 30,000 | |
| Thuringia | Dieter Althaus | 13,000 |
The youth organisation for CDU and CSU is common: Junge Union.
On issues of national importance and in national election campaigns the CDU and CSU closely coordinate their activities, but they remain legally and organizationally separate parties. The differences between the CDU and the somewhat more conservative CSU sometimes lead to friction between them. The most notable and serious such incident was in 1976, when the CSU under Franz Josef Strauß ended the alliance with the CDU at a party conference in Wildbad Kreuth. This decision was reversed shortly thereafter when the CDU threatened to run candidates against the CSU in Bavaria.
The relationship of CDU to CSU has historic parallels to previous Christian Democratic parties in Germany, with the Catholic Centre Party as the national Catholic party in Germany with the Bavarian People's Party as the local Bavarian variant.
The main feature of the logo is, that it always has to be the same: a red inscription 'CDU' (new font) on a white rectangle of proportions 1:3. Any additional symbols (regional symbols) or text have to be outside the white rectangle. If shown on a coloured background this logo is usually shown on an orange field.
The flag is an orange field with the white rectangle at the bottom. The colours are defined in the CI as follows: orange RGB 255/153/0; red RGB 235/39/41.