Pro-slavery and anti-slavery settlers rushed to Kansas, each side hoping to determine the results of the first election held after the law went into effect. ... Opponents of the Kansas-Nebraska Act helped found the Republican Party, which opposed the spread of slavery into the territories.
The first republic to secede from the country of Yugoslavia in 1990 was "Slovenia," although it should be noted that other nations were already considered seceding before this.
D) world war II
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