That the association between tall pointy hats and practitioners of magic started in the 12th century when illustrations in a Zoroastrian book reached Christendom and were taken to show wizards. Later, in the 15th and 16th centuries, tall hats were worn by brewers, which was a typically female profession at the time (you could do it in small batches at home in between feeding the chickens and so on). The tall hats served as advertising in the market place. There was also an association between brewers and magic, because how else do you describe turning water into beer? And also because ale wives were relatively independent women, having their own income – and not least because they spent time getting pissed on their own wares! So the tall brewers' hat became merged with the tall pointy wizards' hat as a witches' hat.
