Final answer:
The Northwest Ordinance provided a framework for adding new states to the United States, banned slavery in new territories, and guaranteed rights and freedoms for settlers.
Step-by-step explanation:
The Northwest Ordinance was historically significant because it provided a framework for adding new states to the United States. It established a process by which territories could become states, specified the conditions for statehood, and guaranteed certain rights and freedoms for settlers in the new lands. The Northwest Ordinance also banned slavery in these territories, except as punishment for a crime.