Maybe I'm missing something here, but I'm pretty sure the American Revolution was conducted as a democratic state under the Articles of Confederation?

I guess I really want to ask this as a followup question: how did the US operate nationally and in the various individual states under the Articles of Confederation? Were state governments determined democratically?

Do the revolutions in Eastern Europe at the end of Communism, such as those in Poland and Czechoslovakia count? I'm somewhat unsure as of course they followed Communism being imposed for decades, which might count as your authoritarian regime.