We conducted a petrologic study of 18 equilibrated eucrites with the goal of understanding the formation and evolution of the crust of asteroid 4 Vesta, the likely source of eucrite meteorites. Their textures indicate that eucrites were basaltic igneous rocks but modified by postcrystallization brecciation, recrystallization, and impact melting. Recrystallized rocks are the most common among clasts in the eucrites; impact melt breccias are rare. Equilibration temperatures of the metamorphic clasts range from 700 to 1000°C, with most in the 800–900°C range. Complex exsolution and recrystallization textures in pyroxenes suggest that eucrites cooled very slowly from high peak temperatures after reheating. This extended period of thermal metamorphism requires a high interior temperature in a Vesta-sized body; this metamorphism could have taken place during and shortly after crust formation. We suggest the crust of Vesta evolved through the eruption, rapid cooling, and subsequent burial and reheating of lava flows. As the crust grew in thickness, the depth of burial increased, causing temperatures to rise and leading to global metamorphism. This resulted in only a small percentage of unequilibrated eucrites (only the last few percent of basalts erupted would not be metamorphosed), and a wide range of metamorphic temperatures and durations for the equilibrated eucrites.