"Reginar I Longneck (c. 850 – 915), Latin: Rainerus 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, Reginars, Reiniers, or Regniers, because of their frequent use of the name "Reginar".
He was probably the son of Gilbert, Count 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." - (en.wikipedia.org 15.12.2019)
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