History is full of dysfunctional families, but few more so than the Carolingian ruling clan. The empire was at the height of its power under renowned ruler Charlemagne. But just two generations later, in the year 841 AD, his grandsons were locked in a vicious contest for power and control. This jockeying culminated in the bloody pitched battle of Fontenoy – a key moment in a civil war that shattered an empire and reshaped Europe, according to Professor Matthew Gabriele and David M Perry in their new book, Oathbreakers. David Musgrove spoke to them to find out more about the shocking aftermath of this crisis.

(Ad) Matthew Gabriele and David M Perry is the author of Oathbreakers: The War of Brothers That Shattered an Empire and Made Medieval Europe (HarperCollins, 2025). Buy it now from Amazon: https://www.amazon.co.uk/Oathbreakers-Brothers-Shattered-Empire-Medieval/dp/0063336677/?tag=bbchistory045-21&ascsubtag=historyextra-social-histboty.

The Carolingian king Lothar II was embroiled in a scandal that destroyed his reign and ended his kingdom – Professor Charles West shares the story: https://link.chtbl.com/v2GgAvSP.

The HistoryExtra podcast is produced by the team behind BBC History Magazine.

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