Final answer:
The Northwest Ordinance of 1787 was the legislation that created the first organized territory in the United States and established the process for dividing it into new states. It also prohibited slavery in the territory, except as a punishment for a crime.
Step-by-step explanation:
The legislation of the Congress of the Confederation that created the first organized territory of the United States and established the process for dividing it into new states was the Northwest Ordinance of 1787.
Under the Northwest Ordinance, a territory could become a state when its population reached 60,000. Additionally, the Northwest Ordinance prohibited slavery in the territory, except as a punishment for a crime.