The metallicity distribution of stars in a galaxy encodes details about the interplay between gas and star formation. For example, gas accretion tends to make a narrowly peaked distribution, whereas ram pressure stripping sharply truncates the distribution. I will present Keck/DEIMOS measurements of the metallicity distributions of dozens of Milky Way satellite galaxies as well as isolated dwarf galaxies in and around the Local Group. The diversity of metallicity distributions illustrates that galaxies can take a multitude of paths to arrive at the same stellar mass and average metallicity. Some of the distributions are easily explained by analytic models of chemical evolution, but many basic questions remain unanswered.