You'll Never See Creepier Masks and Helmets Than These
#11 is appropriately named. We can't believe people actually treated each other in such a way.
Though now associated with Spanish Easter observances, particularly Holy Week, their origin lies in medieval society. Clowns wore them to depict foolishness, and criminals were forced to wear them for the same purpose. For Holy Week sinners wear them with mask as a form of penance.
These masks were once worn by authority figures in the Congo. Different designs served different functions and their shapes, colors, symbolism, and names reflected this, referencing diseases, animals, mysticism, and other phenomenon as a way to wield power over these things.
Also known as the silence hood, this was used to punish prisoners at the Melbourne Gaol prison from 1845 to 1929. Reserved only for those held in solitary confinement, the establishment's rules didn't allow for prisoners to speak to each other. This mask forced such silence.
A form of punishment originating in the 1500s, this device was used on those with a “troublesome tongue,” usually women (though occasionally used on slaves in 18th century Virginia as well). A studded metal piece sticks into the mouth while the rest locks together, making speech incredibly difficult.
Hall and Reed's Escape Apparatus
You probably saw this in 2015 attached to a claim that it portrayed child prisoners of the Nazis wearing gas-testing suits. That's obviously not true, and the nature of these suits and helmets are totally harmless—to aid in escaping submarines. But that doesn't make it any less strange looking.
A World War I gas mask used by the British, the mask features two eye pieces (improved from the previous mask's single visor) and had a layer of cloth dipped in chemicals to protect against chlorine and phosgene and hydrocyanic acid.