Konrad Hermann Joseph Adenauer (German: [ˈkɔnʁaːt ˈʔaːdənaʊɐ] (listen); 5 January 1876 – 19 April 1967) was a German statesman who served as the first Chancellor of the Federal Republic of Germany (West Germany) from 1949 to 1963. He was co-founder and first leader of the Christian Democratic Union (CDU) (until 1966), a Christian Democratic party that under his leadership became one of the most influential parties in the country.

In the early years of the Federal Republic he switched focus from denazification to recovery and led his country from the ruins of World War II to becoming a productive and prosperous nation that forged close relations with France, the United Kingdom and the United States. During his years in power, West Germany achieved democracy, stability, international respect and economic prosperity ("Wirtschaftswunder", German for "economic miracle").

Adenauer belied his age by his intense work habits and his uncanny political instinct. He displayed a strong dedication to a broad vision of market-based liberal democracy and anti-communism. A shrewd politician, Adenauer was deeply committed to a Western-oriented foreign policy and restoring the position of West Germany on the world stage. He worked to restore the West German economy from the destruction of World War II to a central position in Europe, presiding over the German Economic Miracle together with his Minister of Economics, Ludwig Erhard. He was a driving force in re-establishing national military forces (the Bundeswehr) in West Germany since 1955. Adenauer opposed rival East Germany and made his nation a member of NATO and a member of the Western Alliance.

Adenauer, who was Chancellor until age 87, was dubbed "Der Alte" ("the elder"). British politician and historian Roy Jenkins says he was "the oldest statesman ever to function in elected office." He remains the oldest head of government for a major country.

A devout Roman Catholic and member of the Catholic Centre Party, he was a leading politician in the Weimar Republic, serving as Mayor of Cologne (1917–1933) and as president of the Prussian State Council (1922–1933).