Roman triumphal practices changed significantly at the start of the imperial period when the "princeps" Augustus decreed that triumphs and triumphal honours were to be confined to members of the Imperial family; in practice, this meant the ruling emperor or his antecedents. The term "fornix" was replaced by "arcus" (arch). While Republican "fornices" could be erected by a "triumphator" at his own discretion and expense, Imperial triumphal arches were sponsored by decree of the senate, or sometimes by wealthy holders of high office, to honour and promote emperors, their office and the values of empire. Arches were not necessarily built as entrances, but – unlike many modern triumphal arches – they were often erected across roads and were intended to be passed through, not around.