What reasons did France have for favoring the Colonies over England in the war? Specifically, what was the nature of Franco-British relations by the 1770s?

The treaty of Pairs brought an end to the Franco British rivalry and the seven years war.

Explanation:

France lost to British in the seven years war and New France was lost to British. After some years France again began all its efforts to rise in power by taking advantage of creating dominance in the borders of north America and colonizing it. But again it was attacked by the British and north america was saved from France dominance.

The outcome of the Seven Years War created the conditions for both the American War of Independence. France was a rival to the British and when America rose against British, France gave its friendly hand to the Americans from the beginning till the end.