Tremissis (Coin) of Leo III

From the Art Institute of Chicago record

Coins were an ideal way for Byzantine emperors to circulate their images throughout the empire and beyond, since they were used to pay for imported merchandise and to pay foreign mercenaries. They could also be employed as powerful vehicles for propaganda, promoting dynastic succession and emphasizing the earthly emperor’s god-given right to rule. Leo III (r. 717–41) chose to have an image of himself holding a globe surmounted by a cross on both sides of his coin. From the fourth century on, the solidus was the preferred gold coin issued by Byzantine emperors. The solidus remained essentially unaltered in weight and purity until the tenth century. This coin depicting Leo III is a tremissis, worth one-third of 1 solidus.