the magistrate who governs during an interregnum.

This magistrate was established in old Rome, and was almost as ancient as the city itself; after the death of Romulus there was an interregnum, of a year, during which the senators were each interrex in their turn, five days a piece.

After the establishment of consuls and a commonwealth, though there were no kings, yet the name and function of interrex was still preserved; for, when the magistrates were absent, or there was any irregularity in their election, or they had abdicated, so that the comitia could not be held; provided they were unwilling to create a dictator, they made an interrex, whose office and authority was to last five days; after which they made another. To the interrex was delegated all the regal and consular authority, and he performed all their functions. He assembled the senate, held comitia or courts; and took care that the election of magistrates was according to rules. Indeed at first it was not the custom of the interrex to hold comitia, at least we have no instance of it in the Roman history. The patricians alone had the right of electing an interrex; but this office fell with the republic, when the emperors made themselves masters of everything.