What happened
The Royal Frankish Annals, the semi-official chronicle of Charlemagne's court, describe a sky event at the hilltop fortress of Sigiburg in 776, during the Saxon wars. Rebel Saxons had already tricked the Franks into abandoning Eresburg and destroyed its walls, and they moved on Sigiburg. Their catapults did more damage to themselves than to the garrison, and they began preparing an assault. On the day of the attack, the chronicler says, the 'glory of God' appeared openly above the church inside the fort. Many people, both outside and inside, saw what looked like two shields, red in colour, flaming and moving to and fro above the church. The Saxons panicked and fled, and many were killed by their own comrades' spears in the crush. The Franks pursued them to the river Lippe. The Annals insist the witnesses could still be found: many of those who saw it 'remain to this day'.
The original account
apparuit manifeste gloria Dei supra domum ecclesiae, quae est infra ipsum castrum, videntibus multis tam aforis quam etiam et deintus, ex quibus multi manent usque adhuc; et dicunt vidisse instar duorum scutorum colore rubeo flammantes et agitantes supra ipsam ecclesiam.
Annales regni Francorum, s.a. 776 (Latin, public domain), via The Latin Library
The official explanation
In a 2015 study, the Jena astronomers Dagmar and Ralph Neuhauser argued that the 'inflamed shields' of 776, which had been catalogued as an aurora, were most likely a halo display: two mock suns (parhelia) on either side of the Sun. They placed it among other mid-770s reports that also fit halo optics. Historians add that the passage is a bracketed later addition in the Annals and is openly propagandistic, a miracle story showing God fighting for the Christian Franks against pagan Saxons.
The anomalous case
For an 8th-century source the report is unusually well documented. It comes from the official annals of the Carolingian court, not a monastic legend. It names a specific place, a specific church and a specific military situation. It stresses that many witnesses saw it from both sides, besiegers and besieged, and that many of them were still alive when it was written down. The objects are described as two discrete shield-shaped forms, red, flaming and moving back and forth over one building. The halo explanation requires two stationary mock suns, which do not move to and fro, sit at a fixed angle from the Sun, and do not hang over a particular roof. Ufologists from the 1950s onward cited the account because it has a localised position, movement, multiple witnesses and a measurable effect on a battle.
The strongest argument that this was something genuinely unknown or classified, with each claim attributed to the person who made it.
Documents
- Annales regni Francorum (Latin text) report, thelatinlibrary.com
- The years 775 to 776 from the Annals of the Kingdom of the Franks (English) report, deremilitari.org
Sources
- Annales regni Francorum The Latin Library
- The years 775 to 776 from the Annals of the Kingdom of the Franks De Re Militari
- Presumable European aurorae in the mid AD 770s were halo displays (Neuhauser & Neuhauser) arXiv
- Hohensyburg Wikipedia
Witness reports elsewhere
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