The main historical significance of the French and Indian War is that it helped bring about the American Revolution.
Before the French and Indian War, American colonists were relatively content to be British. The British more or less left them alone to tend to their own affairs. They were also aware that the British were their defense against the French in Canada. For these reasons, they had no desire to be independent. After the war, this changed.
The war expelled the French from North America. In doing so, however, the British incurred massive costs. They wanted the colonies to help to defray those costs. Therefore, they started taxing the colonies and doing more to enforce British law in the colonies. These acts made the colonists unhappy. In addition, with the danger of French invasion removed, there was less need for British protection.
For these reasons, the American colonists started to feel unhappy about British rule after the French and Indian War. Their resistance to British actions brought reprisals from Britain which further strengthened colonial grievances. This cycle led to the coming of the Revolutionary War not much more than 10 years after the end of the French and Indian War.