In creating the world of The Eagle, the costume and production designers paid attention to every little detail, from masks to make up.
To create the artifacts for the Seal People, the filmmakers had to also divine the culture, religion, economy, etc of these fictional People According to production designer Michael Carlin, “The seal People are hunter gatherers living largely off the sea, without agriculture or metal technology. They are inspired by very early Britons, and other hunter gatherers that lived across the North Atlantic islands, North America and the arctic particularly the mammoth hunters of the Paleolithic era and Inuit people. Fiercely independent we imagine they have deliberately turned their backs on the technological advances of Rome and southern Britons choosing to live as they have always done.” As for their weapons, Carlin highlights the double-sided as being “imagined to be largely ceremonial. It’s an elongated version of the stone axe that the seal people carry but has 2 opposing walrus tusks instead of the standard stone blade. The shaft is decorated with shells and seal teeth bound with sinew and blood. The teeth that dangle from the shaft rattle when the object is shaken in tribal ceremony.” Costume designer Michael O'Connor further explains how Rosemary Sutcliff’s book inspired some aspects: “This is “The Horned One’s’ mask and antlers. It is based on death masks found throughout Britain and Europe. The Seal People worshiped a god, the ‘horned’ one. In the original book it is well described.”