From a novel written between 1805 and 1815, the events described are set around 1722.
As far as Lyon his journey was not troubled by any untoward incident. But on leaving that town with his post horses he was overtaken by a chaise which, being lighter, arrived at the post house before him. Reaching there a few minutes later ... he at once took up his sword and, going up to the traveller, asked him for the honour of a brief conversation. ...
My father said to the traveller, 'Seńor, your carriage overtook mine and arrived at the post house before me. This act, which does not in itself constitute an insult, nonethless has something disobliging about it for which I feel obliged to ask you for an explanation.'
The colonel was very taken aback by this and placed the blame on his postilions...
'Seńor Caballero,' continued my father, 'I also do not wish to make anything serious of this. And so I shall be satisfied by first blood.' In saying this he drew his sword.
'One moment,' said the Frenchman. 'It seems to me that it was not my postilions who overtook yours but rather yours who by lingering fell behind mine.'
But it's too late, the sword has been drawn and so they duel. But only to first blood, not death.
Swords are not very commonly carried nowadays, but the psychology seems similar...
