In 1787 leaders of the states gathered to write the Constitution-a set of principles that told how the new nation would be governed.
The leaders of the states wanted a strong and fair national government. But they also wanted to protect individual freedoms and prevent the government from abusing its power. They believed they could do this by having three separate branches of government: the executive, the legislative and the judicial. This separation is described in the first three articles, or sections, of the Constitution.