Little more is known of them beyond their mention by Tacitus, who described the Harii as:
Slender links with the Heruli are sometimes made by modern enthusiasts, based on an imagined etymological equivalence.
Pliny and Tacitus (circa 95 CE) both mention Suebian tribes called Harii or Hirri. When Silinga, daughter of the last Heruli king Rhodoulph ("Honor-Wolf"?), married Wacho, king of the Lombards (died 539), as his third polygynous wife, she named her son by him Walter ("Walt-Hari", "ruler of the warriors"). Three classical sources, Procopius, the anonymous 7th century Origo gentis Langobardorum, and Paulus Diaconus, mention this episode. [Also note that the common name Harold is identical as well, from Hari-Walt.].
Germanic harjaz is derived from the Proto-Indo-European root *koryos (alternatively korios, koros), meaning warrior, and is related to Old Persian kara (host), Hittite kuriwanas (troop leader, governor), Greek kouros (young nude warrior) and koiranos (captain), Middle Irish cuire (troop), Gothic harjis (army, marauder band), Lithuanian kare (army), Old Prussian karjis (troop), and Old English here (harrier) [see Stuart Mann's An Indo-European Comparative Dictionary].