Douzeper

Also kynge Charlemayne kynge of Fraunce / With his dyssypers Rowland and Olyuer / With all the resydue of his alyaunce / That in all armes so noble were / On goddys ennemyes brake many a spere / Causynge them to flee to theyr grete vylony / Hardynes was cause that they had vyctory

Source: wiktionary

[T]hou art one of the Douze peers already, and fate has forestalled our intended promotion. Yet rise up, sweet Sir Oliver Thatchpate, Knight of the honourable order of the Pumpkin—Rise up, in the name of Nonsense, and begone about thine own concerns, in the devil’s name.

Source: wiktionary

Ferumbras, despising Oliver’s youthful appearance, tries to frighten him[…]; asks him to describe Charles [i.e., Charlemagne] and the douzeperes[…]; and enquires his name[…]. Oliver declaring himself to be a poor knight, Ferumbras derides him, and bids him return and send Roland, or another of the douzeperes[…].

Source: wiktionary

Cortine, Corteyne, or Cortayn was the name given to the sword of Ogier, one of the celebrated Douzeperes of Charlemagne.

Source: wiktionary