I suppose my question is encompassing the entire history of capes, so people who are studying different time periods can comment on the function and social implications of wearing one.

Why were capes popularized? What was their original purpose? Did that original purpose remain their main function throughout history or did time also change the purpose of the cape?

I hear from someone that capes were worn so when you went to the bathroom in open areas, you could hang it up and get privacy. This seemed to make sense to me, however, why would nobles need capes then? They often had private bathrooms and even some wealthier non-nobles would have private bathrooms.

So what is the actual function of the cape?

(You can answer in whatever time period you know most about)