Between 367 and 370 AD, Emperor Valentinian I had a late antique fort with a floor area of 164*159 m built over part of the deserted ‘vicus’ as part of border security measures.
As early as the beginning of the 5th century, probably in 406/407, the Valentinian fort was destroyed for the first time by Germanic tribes advancing across the Rhine, with the exception of the defensive wall, and set on fire.
Shortly afterwards, troops were stationed in the fort again, but this time they were East Germanic federates (Burgundians?). This second period of the fort also came to an end with a fire and systematic destruction. In 425 at the earliest, but probably not until after 437, troops once again occupied the Alzey fort for a short time. However, the barracks buildings were not rebuilt for this ‘last stand of Rome’ to defend the Rhine border. Instead, brick-roofed ‘Roman’ military barracks were erected inside the fort.
