How did the Northwest Ordinance create tensions between the British and American settlements?

The Northwest Territory, which was gained by England after the Seven Year War with France with the singing of the Treaty of Paris, became a land of interest to both British and American settlers. However, in 1763, the British Crown denied access to any new European settlers and this limit new settlements in the 13 colonies from the Appalachian mountains to the Atlantic. This created great tension among the colonials who wanted to move to the west. When the American Revolution ended and the new nation signed the Treaty of Paris in 1783, tension increased between colonials and European settlers whose lands overlapped. With the newly formed United States claiming and taking control of the lands that had once belonged to British settlers.

When the Northwest Ordinance was signed by the new Congress of the Confederation in 1787, the Territory of the Northwest was created and it gave access to new settlers to lands beyond the Appalachian Mountains, between what was British North America and the Great Lakes and the Ohio River as limit in the South. This Ordinance led to massive movements of American settlers to these new lands and upset the balance with British settlers and also with the Native Americans in the land.