Helmets are among the oldest forms of personal protective equipment and are known to have been worn by the Akkadians/Sumerians in the 23rd century BC, Mycenaean Greeks since the 17th century BC, the Assyrians around 900 BC, ancient Greeks and Romans, throughout the Middle Ages, and up to the end of the 17th century by many combatants.Their materials and construction became more advanced as weapons became more and more powerful. Initially constructed from leather and brass, and then bronze and iron during the Bronze and Iron Ages, they soon came to be made entirely from forged steel in many societies after about 950 AD. At that time, they were purely military equipment, protecting the head from cutting blows with swords, flying arrows, and low-velocity musketry.
Military use of helmets declined after 1670, and rifled firearms ended their use by foot soldiers after 1700 but the Napoleonic era saw ornate cavalry helmets reintroduced forcuirassiers and dragoons in some armies which continued to be used by French forces during World War I as late as 1915.
World War I and its increased use of artillery renewed the need for steel helmets, with the French Adrian helmet and the British Brodie helmet being the first modern steel helmets used on the battlefield, soon followed by the adoption of similar steel helmets, such as the Stahlhelm by the other warring nations. In the 20th century, such helmets offered protection for the head from shrapnel and fragments as well as for specialist roles such as Paratrooper helmets.
Today's militaries often use high quality helmets made of ballistic materials such as Kevlar and Aramid, which offer improved protection. Some helmets also have good non-ballistic protective qualities, against threats such as concussive shock waves from explosions.
Many of today’s combat helmets have been adapted for modern warfare requirements and upgraded with STANAG rails to act as a platform for mounting cameras, video cameras and VAS Shrouds for the mounting of Night Vision Goggles (NVG) and monocular Night Vision Devices (NVD).
Beginning in the early 20th century, combat helmets have often been equipped with helmet covers to offer greater camouflage. There have been two main types of covers, mesh nets were earlier widely used, but most modern combat helmets use camouflage cloth covers instead of the earlier net covers.
By the late 20th century, starting in the 1970s and 1980s, new materials such as kevlar and aramid began replacing steel as a the primary material for combat helmets, in an effort to improve weight, ballistics protection, and protection against head injuries caused by blasts. This practice still continues into the 21st century, with further advancement and refinements in the fibers used, design and shape of the helmet, and increased modularity. Early helmet systems of this new design are the American PASGT, the Spanish MARTE, the Italian SEPT-2 PLUS, and British Mk6.