Given how entrenched the slave trade was at the time, it is remarkable that a campaign to abolish it which began in 1787 succeeded only two decades later.

ECONOMIST: Slavery

Meryl Streep's remarkable portrayal of "The Iron Lady" brilliantly captures the politician I remember and charts the immensity of her achievement in becoming Britain's first and, more than three decades later, only woman Prime Minister.

BBC: The Iron Lady

He created an event that would spur business opportunities not only for teams, but also networks, some four decades later.

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Several decades later, the Civil Rights Act of 1964 and Voting Rights Act of 1965 only came about because local activists, led by prominent leaders such as Rev.

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Yet controversy has long swirled around habeas corpus on the question of whether it is aimed at assuring only that certain procedures be followed, or whether a case can be revisited, years or even decades later, if evidence arises that a convict turns out to be demonstrably innocent.

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