The Pompeian Styles are four periods which are distinguished in ancient Roman mural painting. They were originally delineated and described by the German archaeologist August Mau (1840–1909) from the excavation of wall paintings at Pompeii, which is one of the largest groups of surviving Roman frescoes.
The wall painting styles have allowed art historians to delineate phases of interior decoration leading up to the eruption of Mount Vesuvius in 79 AD between stylistic shifts in Roman art during late Republican and Augustan periods.
The four main styles of Roman wall painting defined are: structural (or incrustation), architectural, ornamental, and intricate. Each style following the first contains aspects of the previous styles. The first two styles (incrustation and architectural) were from the Republican period (related to Hellenistic Greek wall painting) and the last two (ornamental and intricate) from the Imperial period.[1]