The great helm or heaume, also called a bucket helm or barrel helm, is a type of helmet from the High Middle Ages, which emerged in the late 12th century, in the context of the Crusades and remained in use until the 14th century. It was used by knights and heavy infantry in most European armies (1220 and 1540 AD).
In its simplest form, the great helm was a cylinder with a flat steel top that completely covered the head. It had tiny openings for the eyes and mouth.
Years later, the top evolved into a conical shape and gave rise to the 'Sugarloaf helm'. In Spanish, it was called the Zaragoza helm, in reference to the city where they were first introduced in the Iberian Peninsula. Later it was used in the Reconquista and there is evidence of them in the Conquest of Mallorca.
Although the great helm offered superior protection to earlier helmets, such as the nasal helm and the spangenhelm, the knight's peripheral vision was limited, it was heavier, and its shape, with a flat top and no ventilation holes, provided poor ventilation and heated up quickly in warm climates.
Knights often wore the great helm over a coif (hood) sometimes combined with a close-fitting iron cap known as a cervelliere.
The great helm was often blackened, lacquered or painted, and adorned with:
Crosses and Symbols (ventilation areas)
Horizontal and vertical crosses (visor)
Crowns, feathers, plumes (as in the helms belonging to the Military Orders).
Certificate of Origin and Quality. Made in Toledo.