If you look up industrial accidents with nitrogen, it isn’t at all like the accounts of that execution. It takes one breath of pure nitrogen and you’ll just fade out. There have been plenty of accidents where someone connected a respirator up to nitrogen and put it on, and they passed out immediately and didn’t even know to take it off. If you are trying to hold your breath for as long as you can, it is very painful as the buildup of CO2 in the body is what triggers us to breathe.

It actually comes from WW1 where American soldiers thought that French speaking Belgians were French.