A morion is a type of open helmet used during the 16th and early 17th centuries, usually having a flat brim and a crest from front to back. The morion, though generally identified with Spanish conquistadors, was common among foot soldiers of all nationalities, including the English; the first were issued during Edward VI's reign. Inexpensive production costs aided its popularity and dissemination although officers and elite guards would have theirs elaborately engraved to display their wealth and status.
The crest or comb on the top of the helmet was designed to strengthen it. Later versions also had cheek guards and even removeable faceplates to protect the soldier from sword cuts.
The morion's shape is derived from that of an older helmet, the Chapel de Fer, or "Kettle Hat. Other sources suggest it was based on Moorish armor and its name is derived from Moro, the Spanish word for Moor.
In England this helmet (also known as the pikeman's pot) is associated with the New Model Army, the first professional military. It was worn by pikemen, together with a breastplate and buff coat as they stood in phalanx formation, protecting the flanks of the unarmored musketeers.
It provided protection during the Push of pike maneuvers known for their high casualty rate. Although mostly issued to Cromwell's troops many cavaliers wore the morion as well, leading to confusion in battles; soldiers risked being shot by their own allies. It was for this reason uniforms were introduced to identify armies. First these were simple colored sashes but soon the roundheads introduced colored coats which were retained by the army after the 1660 Restoration of Charles II of England.
Surviving morions from the 1648 siege have been unearthed and preserved at Colchester Castle along with a lobster tail pot, a helmet associated with Oliver Cromwell's heavily-armored Ironside cavalry.