Thanks for your feedback.
In hindsight the whole logline is too convoluted and I tried to squeeze too much in it.

Maybe I should have made it shorter:
“When in the Early Middle Ages a megalomanic business mangate and breeders of Raptors team up to conquer the Holy Roman Empire, only Charlemagne’s Elite troop The Scara stands in their way.”

The breeders have been exiled to a secluded island generations ago, where there still were dinosaurs, like in Doyle’s “Lost World”. As they could not leave the island, they needed to be freed. (And they brought their feathered, breathing war machines and their lust for vengeance with them.)

I actually put some thought into the year: Charlemagne had to be alive (he died 814), he had to be older, otherwise he would lead the Scara himself, it had to be clear that Louis the Pious was his successor (that means, his other sons were dead already), he was already crowned emperor etc.
Charlemagne is a supporting character and an important figure (historically, but also for this movie), so I wanted to have him in the logline.

PS: There is a “the” too much in the logline, but as I’ve said, the whole logline is suboptimal.