This sauce is ubiquitous in South America, where it is a significant player in the art of churrasco: meat, most often beef, that is grilled over charcoal or a wood fire. Parsley is the traditional base, but cooks vary the herbs and spices. I flavor my green chimichurri heavily with robust, earthy oregano, which is what the gauchos use, according to famous Argentinean churrasco chef Francis Mallman. Chile is not typically added in Argentina, he says, but this seems to be a very purist approach in practice. Pass the sauce at the table or use it as a marinade.
Moreover … It is amusing to note that chile peppers do not grow well in the country of Chile. The climate is too chilly (pardon the pun) for them.