From Seamus Heaney's popular translation of Beowulf, starting line 2401:
The lord of the Geats took eleven comrades
and went in a rage to reconnoitre.
Well, the sense of reconnoitre is a military survey or field intelligence-gathering exercise. Usually patience and caution are the watchwords; you aren't looking for a fight. And in this case the lord of the Geats was not. The idea of conducting one in a blood-lusty berserker rage is farcical, but never mind - in my opinion that is the least of this sentence's transgressions.
I'm sure Heaney's Anglo Saxon is better than mine, but I would not have ended the sentence thus. "Reconnoitre" is jarringly out of place, as a neologism borrowed from French maybe a thousand years after the story took place. (Heaney even went with the French spelling over the anglicized "reconnoiter" - zut alors!)
I know I am being unfair - Heaney's version is in Modern English, of which language "reconnoiter" is a perfectly acceptable member, along with many other words that the original poet would never have recognized, but still get stuffed in his mouth by Heaney and every other scholar who has attempted a translation.
And according to my Anglo Saxon dictionary, the word may have an original Anglo Saxon root; the same that led us to the word "reckon". But tone has to matter for something. Whether the word accurately describes the action or not, I can't imagine someone like Beowulf performing "reconnaissance" - it's too modern, and far too French. I would have expected a poet and man of letter such as Heaney to be more careful.
I'm also pretty sure Beowulf didn't have any "élan", either.
(Edit: I note that many online academic courses and quizzes about Beowulf utilize Heaney's translation and include "reconnoitre" as one of the vocabulary words, so it's good to know that this Anglo Saxon masterpiece is encouraging people to learn their modern French cognates.)