Drogo (17 June 801 – 8 December 855), also known as Dreux or Drogon, was an illegitimate son of Frankish emperor Charlemagne by the concubine Regina.

Aachen was the winter palace of the Carolingian empire located in the north-east section of Gaul, close to the Saxon lands.

Drogo's brother, Hugh, was ordained and served as the abbot of Charroux, St-Quentin, Lobbes, St-Bertin and Noaille.

Forced out of the royal court when Louis the Pious became Emperor in 814, Drogo and Hugh were forcibly tonsured and "put under free custody into monasteries".

Throughout the 830s Louis the Pious was busy with the rebellions of his sons and assorted counts, dukes, abbots, bishops and archbishops.

On his deathbed, Louis asked Drogo to send the royal regalia (crown and sword) to his son Lothar thus indicating the transfer of power.

One could instead see this sepulchre as a sign of archbishop Drogo's ambition of elevating his city of Metz by making it the cradle of the Carolingian family.

In all probability he wished to establish Saint- Arnoul, whose patron saint was a family ancestor, as the royal mausoleum of the Carolingians (see K.U.

The sacramentary would have been used in Metz's Carolingian cathedral and constitutes a precious record of the liturgical practices of the time and the accoutrements used in the liturgy.

This manuscript is one of the monuments of Carolingian book illumination and contains all the prayers which would have been spoken by Drogo, as the officiating priest, during the course of the year.

There is a particularly interesting entry in the Annales Bertiniani: anno 839 "Dominicae nativitatis festum hilariter, a Drogone fratre suo et Metensis urbis episcopo decentissime susceptus, in eadem civitate caelebravit".

["He (Louis the Pious) joyfully celebrated Christmas at Metz, where he had been received handsomely by his brother Drogo, the bishop of that city."]

A list of bishops of Metz records "domnus Drogo archiepiscopus et sacri palate summus capellanus, filius Karoli imperatoris" (Drogo lord archbishop and sacred palace chief chaplain, son of Emperor Charles) as 40th bishop, holding the position for 32 years, 5 months and 7 days.