Anything prior to the start of the Dark Ages is early church as far as I'm concerned. Constantine gave the religion mass legitimacy by converting as he did, thus did the entity gain the political clout to begin 'legally' suppressing other traditions. So when I say 'early church' I tend refer to the authorized state-sponsoered entity, and not necessarily to what they were before Constantine, merely one tradition among others in Roman society. Suppression was certainly happening prior to the 4th century but it was a different dynamic, different congregations competing for dominance as we have now in the U.S. Suppression didn't reach the level of genocide, as happened with the Cathars, until after Constantine. Regardless, the fact remains that dominant religious traditions abused their power, official or not, and left us with a poorer understanding of history where these matters are concerned.