Weizsäcker, a member of German chancellor Angela Merkel's Christian Democrat party, played a major role in Germany's handling of its Nazi past, calling May 8, 1945, a day of "liberation" for his country rather than a surrender.
The first president of a reunited Germany, he played a major role in helping the country face up to its Nazi past. During his 10 years in the office, he did not shy away from thorny political debates such as on integration, and won recognition at home and abroad.
Though the post is largely ceremonial, he became known as the "political president" with a knack for giving stirring speeches that were often shaped by his own history.
In his most memorable address, marking 40 years after the end of World War II, he told lawmakers that May 8, 1945, marked "a day of liberation from the inhuman system of National Socialist tyranny".
He began his military service in 1938, was wounded several times and was close by when one of his two brothers was killed early on in the war. "I buried him myself. I needn't tell you how that feels," he told news weekly Spiegel's online edition in 2009.
After the war he studied law and history and, still a student, assisted the lawyer defending his father Ernst von Weizsäcker, a high-ranking official of Hitler's foreign minister, Joachim von Ribbentrop, at the US-run Nuremberg trials.
His father received a seven-year sentence that was later reduced to five years.
Weizsäcker was born in the southwestern city of Stuttgart on April 15, 1920, the fourth child of an aristocratic family. As his father was a diplomat, he spent his early years in different European cities before
studying at Britain's Oxford University and in Grenoble, southeastern France.
After the war he quickly worked his way up to become the head of the economic policy division at industrial group Mannesmann before moving to Waldthausen & Co. bank, and in 1962 he joined pharmaceutical group Boehringer.
Having already joined the Christian Democratic Union (CDU) in 1954, he was active in both politics and the Protestant Church alongside his professional life. He was elected to the Bundestag lower house of parliament in 1969.
As mayor of Berlin from 1981 until 1984, he became the post's first incumbent to travel to communist East Germany where he met its leader Erich Honecker.
Weizsäcker ran unsuccessfully for president in 1974, but a decade later, in May 1984, with record broad backing, he became Germany's sixth president for a five-year term that saw him speak out on Germany's past, stand up for democratic and Christian values and seek consensus.
He drew attention in particular to the problems of developing countries, unemployment in the world and environmental protection.
Closer to home, he called for reconciliation with East Germany and encouraged dialogue with the communist regime as well as urging reforms under the last Soviet leader Mikhail Gorbachev to be taken seriously.
Just several months before the Berlin Wall fell, he won a second mandate as president in May 1989, this time with even greater support than in 1984, and oversaw German reunification and the end of the Cold War.
On October 3, 1990, the day Germany reunited after more than 40 years, he stressed the importance of a unified approach to the looming challenges, warning that "high-yield loans alone" would not fund unity
"Unifying ourselves means learning to share," he said. Weizsäcker, who had three sons and a daughter with his wife, Marianne, continued to be involved in public life after leaving office.