It wasn't until a good friend started raving about orthodoxy had i ever heard of it apart from Greek or Russian Orthodox, which i just thought was similar to our C of E. I never twigged it was another religion completely and in charismatic circles, i'd never heard it discussed as an option before now. Is that quite common or am i just thick? Whenever we studied <and i use that term loosely> the origins of Christianity, Orthodoxy was never mentioned. Was it always known as this way back when in England?
I guess there's two ways to look at it...
1) There are a couple hundred million Orthodox, and they are (some would say) the 2nd largest Christian Church in the world. Thus you not having heard of them is extremely abnormal.
2) Orthodox visibility in England, US, Australia, etc. is fairly low. The number of Orthodox Christians is also fairly low (e.g., Orthodox are about .3% of the US population)
So... I dunno
I had "never heard of them" until I went looking for a traditional Church, even though I had walked past an Orthodox Church a couple hundred times growing up. Sometimes "never heard of them" really means "never noticed" or "never paid attention". *shrugs*