"Coins have been a major force in helping to advance civilization.... In ancient times, they spread the news of major construction projects, changes in political leadership, and other important events. They have served as mini-newspapers, objects of art, and even sources of propaganda."
Commemorative coins informed the world of significant events, accessions, or conquests. Ancient rulers, like today's, wanted to be in the news much as possible, so they put their names and images on their coinage.
The person who first decided to put news on coinage was a genius of the first water, for he solved the problems of news creation, distribution, and archiving in one fell swoop.
firstname.lastname@example.org (Joel Altman)