[German version] Stands for
s(enatus) p(opulus)q(ue) R(omanus) and was the usual title of the Roman state as embodied in its two governing bodies, the 'Senate and People of Rome' (i.e. not, as in Greece, the people alone, e.g.
hoi Athēnaîoi), from the 1st cent. BC. Before this, the
populus was in first place (first evidence in the decree of Aemilius [I 32] Paullus for Lascuta, early 2nd cent. BC: ILS 15; cf. Pol. 21,10,8). From the time of Augustus, SPQR appears on inscriptions as the author of consecrations (e.g. of buildings and monuments), later also as the recipient of dedications. …