None the less was it to prove, in the end, the decisive factor in the struggle.
The alliance with France altered the whole character of the war, which ceased now to be merely a war in North America.

France soon gained an ally in Europe.

Bourbon Spain had no thought of helping the colonies in rebellion against their king, and she viewed their ambitions to extend westward with jealous concern, since she desired for herself both sides of the Mississippi.

Spain, however, had a grievance against Britain, for Britain would not yield Gibraltar, that rocky fragment of Spain commanding the entrance to the Mediterranean which Britain had wrested from her as she had wrested also Minorca and Florida.

So, in April, 1779, Spain joined France in war on Great Britain.