The line comes from Warcraft III: Reign of Chaos, the 2002 real-time strategy game by Blizzard Entertainment. The Peasant is the basic Human Alliance worker, used to gather gold and lumber and to construct buildings, and he responds with short acknowledgements each time the player selects or moves him. In the French localisation Oui messire became his signature reply, quoted by French players for years. It later spread through soundboards, streams and short edits, where the old strategy voice line is reused far outside the game.
About this sound
The French Warcraft 3 Peasant voice line Oui messire, heard when you select the Human worker unit, now used as a funny yes sir reply in memes and edits.
This is the short French voice line from the Human Peasant in Warcraft 3, who answers Oui messire in a cheerful, eager tone whenever he is given an order. The delivery is polite to the point of comedy, like a loyal medieval servant who is far too happy to chop wood or build a farm. It lasts just a second, but the respectful wording and bright peasant accent make it instantly recognisable to anyone who played the French version, turning a simple yes into a joke about blind obedience.