How come there's only Korean's car brands in Korea?

I went to South Korea this past summer and all I see on the road are Korean's car brands. Yes I know it is South Korea after all and they probably want to buy their own car brands, but I don't see any Toyota, Honda, or Ford. Occasionally I do see some Mercedes here and there but can someone explain to me why 98% on the cars are Korean's brand cars? Is there some kind of embargo against foreign manufacturers?