“We are but of yesterday, and we have filled every place among you--cities, islands…”

We are but of yesterday, and we have filled every place among you--cities, islands, fortresses, towns, market-places, the very camp, tribes, companies, palace, senate, forum

Tertullian · The Apology (Apologeticus) · ANF III, Apology, Chapter XXXVII

Part of an argument that the Christians could ruin the empire by simply withdrawing from it, and choose not to. The boast is rhetorical — the real numbers around 197 were far smaller — and it is quoted for the picture rather than the census.