Overview
Reginar Longneck or Reginar I ( 850–915), or Ragenerus Longicollus, was a leading nobleman in the kingdom of Lotharingia, variously described in contemporary sources with the titles of count, margrave, missus dominicus and duke. He stands at the head of a Lotharingian dynasty known to modern scholarship as the Reginarids, because of their frequent use of the name "Reginar".
Background
Reginar was probably the son of Giselbertus, comes of the Maasgau, and a daughter of Lothair I whose name is not known (Hiltrude, Bertha, Irmgard, and Gisela are candidate names). In an 877 charter in the Capitulary of Quierzy, he possibly already appears as "Rainerus", alongside his probable father as one of the regents of the kingdom during Charles the Bald's absence on campaign in Italy.
Career
Reginar was lay abbot of important abbeys stretching from the Meuse to the Moselle through the Ardennes, Saint-Servais in Maastricht, Echternach, Stavelot-Malmedy, and Saint-Maximin in Trier. All these abbeys lay on or near the boundary negotiated between the Eastern and Western Frankish kingdoms in the Treaty of Meerssen in 870, during a period when the Western Kingdom controlled much of Lotharingia. In Echternach, he was referred to as "Rainerus iunior" because the lay abbot before him, a probable relative, had the same name.
Reginar's secular titles and activities are mainly only known from much later sources which are considered to be of uncertain reliability. Dudo of Saint-Quentin, in describing the great deeds of the early Normans, calls Reginar I (who, along with a prince of the Frisians named Radbod, was an opponent of Rollo, the founder of Normandy) a duke of both Hainaut and Hesbaye. Centuries later William of Jumièges, and then later still, Alberic de Trois Fontaines followed Dudo using the same titles when describing the same events. He was variously referred to as duke, count, marquis, missus dominicus, but historians doubt that these titles were connected to a particular territory. That he called himself a duke is known from a charter at Stavelot 21 July 905, but this was during a period when Gebhard was duke of Lotharingia.
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