Wow, tough question. Perhaps Cleopatra. Unfortunately, countless women have toiled in obscurity since the dawn of history so we will never know their name or their accomplishments.
Since you have a interest in this topic, you might enjoy the book Daily Rituals, Women at Work by Mason Currey. This is his second book about the work habits of famous authors, composers, scientists, artists and so on. The first one has been out for a few years now so you probably could find it on Ebay for just a few bucks. The one I mentioned just came out this month.