Schmidt led then-West Germany from 1974 to 1982 as it rose to become a global economic powerhouse.
A centrist from the Social Democratic Party (SPD), Schmidt steered the country through a bloody wave of terror by far-left radicals from the Red Army Faction (RAF), preached free-market economics to his party and embodied cool-headed pragmatic politics in a Europe riven by the Iron Curtain.
Leading tributes to the man she described as "a political institution of our country", German Chancellor Angela Merkel said Schmidt was "an authority whose advice and judgment meant something to me".
French President Francois Hollande simply called him "a great European".
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Co-publisher of the influential liberal weekly Die Zeit, Schmidt continued to play an active part in international economic debate, including criticising Merkel during the eurozone debt crisis for lacking financial savvy.
He was a popular guest on television chat shows, always granted special dispensation to flout a smoking ban while holding forth with the laconic brand of wit prized in his native port city of Hamburg.
German media recently grouped him among "Russia apologists" after he expressed understanding for President Vladimir Putin's actions in Ukraine.
As a political commentator, conservative daily Die Welt said, Schmidt's "bite and punchline" earned him great respect across the political spectrum.