great helm

The great helm of the High Middle Ages arose in the late 12th century in the context of the crusades and remained in use until the 14th century. They were used by knights and heavy infantry in most European armies. In its simplest form, the great helm was a flat-topped cylinder of steel that completely covered the head and had only very small openings for the eyes and mouth. Later designs gained more of a curved design, particularly on the top, to deflect or lessen the impact of blows.The style is sometimes referred to as a 'crusader helmet', but also as a 'pot helm', and a later variant with a more conical top is known as a 'sugarloaf helm'. In Spanish they are yelmo de Zaragoza, referring to Saragossa where they were introduced for the first time in the Iberian peninsula.
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A fully enclosed defense for the head developed during the 12th century. Known also as the "barrel" or "pot" helmet (modern terms), the heaulm was generally made from several smaller sheets of steel , completely covering the face. From manuscript accounts it appears that they were often painted in the colors of the knight, and might also have been washed in gold or adorned with brass, bronze or latten decor, generally in the form of a cross under the occularia and down the front of the face.