When Constantine the Great became the first Roman emperor to convert to Christianity 18 centuries ago, its historicity had a cascading effect on the looks of the coins. Thus, starting from the early 4th century AD, most of the kings flaunted their religious allegiance on the legal tender the subjects used in their part of the world. That became the general trend for some 300 years—until the coinage practice in the Middle East chose to avoid representations of either kings or their religious symbols.