The country that joined the French at that time was Spain, who controlled the area of what is now Florida. The Iroquois were on the French side but were allies the entire war and not a "European country".
Spain will enter in 1779 as an ally of France. The following year, Britain will declare war on the Dutch who have been engaging in profitable trade with the French and Americans.
Spain joined the Revolutionary War as an ally of France in 1779, supporting the American colonies against Great Britain. Their involvement was strategic, aiming to weaken British power while securing Spanish interests in the Americas. Although Spain did not sign a formal alliance with the Americans, they provided crucial support and resources during the conflict.
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