What comes closest to what people view as the stereotypical knight that is commonly thought of? Is there any specific unit in the early 10th-14th centuries that resemble the knight? What country did they come from? What was their armor and weaponry like?
( All of this excluding units like the Knight's Templar)
Can you describe what you think the archetypical knight looks like? What type of armour does he wear (mail or plate?), what does he wear over his armour, if anything, what is his horse wearing, what is he carrying?
There are a number of archetypical images of knighthood, so it is hard to tell which one you are talking about.