A belief is an assumed truth.
Hence everything is a belief – including this statement.
A belief is the mental attitude that some proposition is true. For every given proposition, every person either has or lacks the mental attitude that it is true.We create beliefs to anchor our understanding of the world around us and so, once we have formed a belief, we will tend to persevere with that belief.
Beliefs are important because behavior is important and your behavior depends on your beliefs.
Is the culture of a country / race / region entangled with the beliefs prevailing in that region ?
I don’t want to add to the contoversy, but the dress code for men looks a lot like how hindu pilgrims wear on their devotional journeys. Maybe pre-islamic Arabians would dress similarly for pilgrimages. Why is a different from usual dress code enforced?
Like Tawaaf was common in Hindu deity placed in Hinglaaj (an area on the border of Sindh and Balochistan). What about the touching and kissing Hajr e Aswad (black stone)?
This is exactly right. For example, the “4 wives” issue is controversial in a monogamous world, but 6th century Arabs used to have up to 8 or 9 wives, so 4 was actually them practicing restraint. Stating this isn’t haram or anything, just a fact.
and you sum up in one sentence 
