Excuse my French

What is the origin of this phrase and what do French speakers say instead?

Previous thread.

Thanks. Shoulda searched.

As to what the French use instead, well, there’s no direct equivalence ; that is to say, we don’t attribute coarse language to some other nationality. The canned phrases used in the same circumstances are “si je puis me permettre” (lit. “If I may allow myself”) or “passez moi l’expression” (“overlook/forgive my saying so”)

Sacred blue!

That sounds close to the more popular version I’ve heard in English: “Excuse me for saying this, but…” I’ve especially heard it a lot from (U.S.) Southerners.