Just to get the nomenclature straight...a doo-rag was/is what an African American dude would wear to keep his hair in position after he's gotten a "process job"...I believe that the expression that I heard in my youth was something like "...lyed, fried and slicked to the side". Anyway, a lot of guys would cultivate a pompador and the doo-rag would hold it up in place during non-critical times (like when you were at work) and be removed when one wanted to look good (like when you went out on weekend evenings). The light weight bandana head covers worn nowadays are descendants of those original doo-rags. Think Little Richard back in the day...

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AA