This is a bit difficult- a caste system is inevitably going to change and modify itself over centuries. In India, for example, the caste system varied wildly from place to place and time to time
True and caste system in India hasn't been always very strict. It became stricter during British colonial era.
I could imagine a super-feudalist system that basically makes it the law to follow the fathers proffession. However, if mercentalism and colonialism come about, I can see its demise.
One caste system that existed to modern times was the Jewish Ghetto. Another one would be the treatment of gypsies.
True and caste system in India hasn't been always very strict. It became stricter during British colonial era.
I'd think our society would resemble OTL China, Japan or India.
To a point, as far as gypsies go, it is unofficially in place in not few parts of Europe. Though I would not call it really a "caste" system. However, AFAIK the gypsies and some related groups are thought to have sort of originated out of the Indian caste system...
I thought one aspect of the caste system was that in many occasions the different caste speaks a different dialect if not different language entirely. Or were even made up of foreigners. Part of the attitude of a caste system is that the lower people are not only low class but culturally and racially different.
Also for a European "Untouchable" caste maybe these guys would count:
http://en.wikipedia.org/wiki/Cagots
Why? Any reasoning behind this or just vague thoughts?
Because India is the caste society of OTL, and China and Japan are pretty hierarchical too.
For the "WI" part, this would have huge implications when, in OTL, colonial expansion started becoming more long-range and a big source of wealth. If your peasants are tied down to your land or to certain jobs they certainly can't just randomly decide to become sailors looking for a better life. Assuming that there was no chance to improve their condition, they would probably not have that incentive either.