The Shadow Men or Shadowmen are the people settled along the mountainous region of Essos known as the Shadow Lands, in the Further East of the known world. Shadow Men are known for covering their bodies in tattoos and wearing red lacquered wooden masks.
A Game of Thrones
During her stay at Vaes Dothrak to be presented to the dosh khaleen, Daenerys Targaryen often spends her mornings in the Eastern Market. She enjoys watching the people there, including dour and frightening masked Shadow Men.
A Clash of Kings