The first part of the study examines the processes by which religious buildings changed from huts and shrines to monumental temples, and explores apparent differences between these processes in Latium and Etruria. The second part analyses the broader architectural, religious, and topographical contexts of the first Etrusco-Italic temples alongside possible rationales for their introduction. The result is a new and extensive account of when, where, and why monumental cult buildings became features of early central Italic society.