As a young child, Merkel moved with her family to East Germany so that her father, a Protestant pastor, could work in his native Brandenburg. After earning a doctorate in physics at the University of Leipzig in 1978, she settled in East Berlin, where she worked at the Academy of Sciences as a quantum chemist. In 1989 she became involved in the democracy movement, and in 1990, shortly before Germany's reunification, she became a member of the conservative Christian Democratic Union (CDU). Elected as a Bundestag (lower house of parliament) deputy later that year, she became noted for her political skill. Chancellor Helmut Kohl (Kohl, Helmut) made her minister of family affairs, senior citizens, women, and youth (1991–94) and minister of environment, conservation, and reactor safety (1994–98).

In 1998 Kohl and the CDU lost the elections to Gerhard Schröder (Schröder, Gerhard) and the Social Democratic Party. The following year a finance scandal hit the CDU, and Merkel became a vocal detractor of Kohl, her one-time mentor. Merkel's stance greatly increased her visibility and popularity with the German public, although it upset Kohl loyalists. In 2000 Merkel was elected head of the CDU, becoming the first woman and the first non-Catholic to lead the party. She was also the first CDU leader to come from the party's liberal wing, which was particularly problematic for the CDU's sister party in Bavaria, the ultraconservative Christian Social Union (CSU).

As CDU leader, Merkel faced the lingering effects of the finance scandal and a divided party. In 2002 she ceded the nomination for the general election to Edmund Stoiber (Stoiber, Edmund) of the CSU, who later lost to Schröder. Merkel received the party's nomination for the 2005 election, and among her campaign promises were reforms to the country's ailing economy and improved relations with the United States, which had become strained by Schröder's opposition to the Iraq War. The CDU and CSU won the general election but failed to capture a majority. After several weeks of talks, a deal was reached that gave Merkel the chancellorship in a coalition government. She took office on November 22, 2005, becoming not only the first woman to hold the office but also the first East German.