The "buckle hats" are often associated with the Pilgrims in pop culture, but the real Pilgrims never wore such an item, nor has any such hat ever existed as a serious piece of apparel. However, the Pilgrims did wear the similarly shaped "capotain" hats. This tall-crowned, narrow-brimmed, slightly conical "sugarloaf" hat, usually black, was worn by men and women from the 1590s into the mid-seventeenth century in England and northwestern Europe, and it is especially associated with Puritan costume in England in the years leading up to the English Civil War and during the years of the Commonwealth.

Source: Wikipedia