Tolkien created Rohirric as the fictional language associated with the Riders of Rohan.
Rohirric is the language of the Rohirrim, the horse-lords who live in Rohan in The Lord of the Rings. Tolkien did not present much Rohirric vocabulary directly in the narrative. Instead, he represented it through Old English forms and names, creating the impression that the language of Rohan was historically related to the language of the Anglo-Saxons.
Names such as Éomer, Théoden, Éowyn, and Meduseld draw on Old English influences. “Meduseld,” the golden hall of Rohan, means “mead-hall” in Old English. This linguistic method reflects Tolkien’s fictional translation conceit: the Common Speech is rendered as modern English, while the speech of Rohan is rendered in an older English style.
Rohirric should not be confused with Quenya or Sindarin, Tolkien’s best-developed Elvish languages. It is also distinct from Westron, the Common Speech used widely across Middle-earth.