I’d guess in the last decade, with the explosions of youtube and facebook, well known currently would mean a particular thing (idea, word, tune etc. meme may be a better descriptor) simultaneously resides in the heads of a few million people at least. How many heads would a thing/meme have to have been in say 50 years ago in order to be considered as well known? A century ago? Five hundred years ago? Around the time of Christ? How far back would one need to go before “well known” is on the order of hundreds of people?
I disagree with the basic premise of the question. You can easily have something that is well-known in one area but not in another (such as the mayor or governor of my locality or yours), and other things that are well-known everywhere (such as the leader of the major world superpowers). This is as true today as it was 3000 years ago. Nothing has changed.
Well, maybe some details are more accessible nowadays: Back in the day, everyone knew who Ceasar was, but you probably wouldn’t know his face. Stuff like that.
I’m talking about well known amongst the general human population, not local groups. Still I guess the question could be posed as: what percentage of a population needs to know of a thing/meme before it is considered well known? (then look back at population numbers through the ages to answer the first post)
I doubt whether there is any sensible, general answer. “Well known” is a relative notion, and an extremely vague one at that. Usually, when people say that something is “well known” they are not basing that opinion on any hard evidence, just extrapolating from their personal experience (at best!), and that has probably been as true down the ages as it is now (or maybe not; I have no hard evidence, and there probably isn’t any such evidence, for that either).
Yes, like I said.
But in an attempt to be helpful and informative, I looked up the phrase “well known” in Wikipedia, not really expecting to find anything. I was happily mistaken. It turns out that “well known” is a concept very important to the legal status of a trademark, and is mentioned more than ten times in that Wikipedia article. Unfortunately, it does not give any sort of definition for what qualifies as “well known”, but you might be able to get somewhere by researching other sources regarding trademark law.
Since I doubt there is a simple factual answer to this, let’s move it to IMHO.
Colibri
General Questions Moderator
The “general human population” was divided into local subgroups until well into the 20th century. Europeans knew nothing about Asians, Americans knew nothing about Africans, with the tiniest handful of exceptions.
I agree with the others. Within a sub-group, which could be anywhere from a group of city-states to an empire, rulers and military heroes could be known by millions - and still be invisible to anyone outside that sub-group.
The printing press made other types of celebrities “well known.” Martin Luthor would have been as well known as the Pope within Europe and still probably almost unheard of elsewhere. By the time of the American Revolution Washington’s name would have been understood in European capitals and Ben Franklin was a huge popular with the masses star in Paris when he was ambassador. In India? Not outside the British colonizers.
Newspapers were as powerful 100 years ago as media today. There were nationwide scandals and heroes in America that garnered the equivalent of the 24/7 coverage we see for Trayvon Martin or the Boston bombings. Would they be known even in Europe, though? I doubt it. I know that when I read British books of the period they make references to incidents that would have been as well known to them. I’m supposed to be a historian and I still don’t know what they’re talking about.
I can’t figure out a better way to try to answer this. It’s too general and undefined to do more than circle around and make some general and undefined remarks.