Origins and Name
Herumor belonged by descent to the Númenóreans, the Men of the island realm raised for the Edain in the west of the Great Sea during the Second Age. The passage that names him places him among those of that race whose dwellings lay in the far southern lands, remote from the northern havens that the Elf-friends held. By the later centuries of Númenor its people had divided in temper: a minority kept to the old friendship with the Eldar and reverence for the Valar, while the greater part, the King's Men, turned against that friendship and, once Sauron had been brought captive to the island and had begun to teach there, fell increasingly under his persuasion. The southern settlements grew out of that second current. Herumor's origin is therefore to be sought in Númenor and in its dominions overseas, not among the folk with whom he came to live.
The name itself is Elvish in shape rather than Adûnaic, and it is not a name of Harad. Its first element corresponds to the word for lord that appears in Tar-Herunúmen, the High-elven name of the king who was the first to take the sceptre under a title in the Adûnaic tongue; its second is the dark element familiar from Mordor and from Morgoth, and it recurs in the name of his one recorded companion, Fuinur, whose own first element is that of night or gloom, as in Taur-nu-Fuin. No gloss is given for either name where they occur, so a rendering along the lines of 'dark lord' remains an inference drawn from the elements and not an authorial translation. Nothing in the text explains how a man of Westernesse came by such a name, whether it was borne from birth or taken later; no house, parentage or date of birth is set down with it.
Men of this descent and this allegiance are named elsewhere in Tolkien's writing as the Black Númenóreans, a term used of the kindred that held the southern haven of Umbar and, at the close of the Third Age, of the renegade who spoke for Sauron before the Black Gate. Herumor is not so labelled in the passage where he appears, and he stands at a far earlier point in the reckoning of years; the term is set beside him as a description of his kind rather than as a style he bore. What the two records share is the pattern: men of the high race of the West, settled far from it, whose descent gave them stature among peoples who had none of their history.
History
Everything recorded of Herumor's career is contained in a single sentence of the chapter that carries the Second Age from the making of the Rings to the overthrow of Sauron. There it is said that he and Fuinur rose to power among the Haradrim, and that folk is described as numerous and cruel, holding the wide lands that lie south of Mordor and beyond the mouths of Anduin. How the rise was accomplished is not told: not whether by war, by counsel, by marriage into the ruling houses, or simply by the awe in which men of the high western race were held among peoples who had never seen the sea-kings' ships except as masters. Nor is any use of that power described. The notice carries no year, and its position in a chapter that crosses centuries in a paragraph allows the ascent to be set either in the last decades before the ruin of Númenor or in the disordered years that followed it.
The world in which such a career became possible is better dated than the career itself. Through the middle centuries of the Second Age the Númenóreans passed from bringing gifts and teaching to taking tribute, and their coastal forts in the south hardened into dominions, chief among them the great haven of Umbar. It was there that Ar-Pharazôn landed his host in the year 3261 of that Age, and in the following year Sauron was carried to the island as a prisoner, from which captivity he took the mastery of the King's counsels. Whatever hold Sauron gained over the southern settlements, it worked upon men already accustomed to lordship over the peoples about them. Herumor's break with his own kindred is therefore not an isolated defection but the extreme case of a movement long under way.
The drowning of Númenor in the year 3319 altered the standing of every man of that race living overseas. The island and its fleet were gone, and with them the sceptre whose service Herumor had already put aside; the Faithful who escaped the wreck established their realms in the north and along the Anduin, far from the southern coasts. Sauron's spirit returned to Middle-earth and rebuilt its power in Mordor, and the lands south and east of that country fell increasingly under it. For a Númenórean settled far away among the Haradrim, the catastrophe removed at one stroke both the loyalty he had abandoned and any authority that might have called him to account for abandoning it. That the chronicle names him at all in this stretch suggests his weight among that people was thought worth remembering when nothing else about him was.
The last great event of the Age fell within a lifetime of the notice. Sauron assailed Gondor in 3429 and took Minas Ithil; the Alliance of Elves and Men was made in the following year; the hosts crossed the mountains and fought upon Dagorlad in 3434, and after a siege of seven years Barad-dûr was thrown down and Sauron overthrown in 3441. In that war the peoples of the East and of the South stood for the most part with Mordor, though the division ran through nearly every kind of living thing. Whether Herumor was still living when the summons went out to the Haradrim, whether he led any part of their strength to the Morannon, and whether he died there or long before, is nowhere stated. No death, no battle and no successor is set down for him.
After that sentence the record closes. Fuinur is treated no more fully, and the two are named together once and never again, in a chapter otherwise willing to follow a single line of kings across three ages. The Haradrim themselves continue in the histories as the enduring southern adversary of Gondor: their harbours were reduced when the kings of the South took Umbar in the Third Age, and for a season the Harad paid tribute, but the enmity outlasted every settlement of it, down to the day the mûmakil came north to the Pelennor. Nothing in those later annals is traced back to Herumor, and no house among the southern peoples is said to descend from him. The silence is characteristic of the chapter rather than of him alone; it names what it needs to name for the shape of the Age and leaves the rest unwritten.
Role and Powers
Within the legendarium Herumor functions less as an actor than as a marker. The chapter that names him is concerned with the spread of Sauron's dominion after the Rings were made, and it needs at that point to indicate that the strength gathering in the South was not merely native to it but had drawn in men of the high western race; it does so by naming two individuals and nothing more. What is attributed to him is authority among a people, not any faculty of his own. He is given no title, no seat, no realm, no army with a number, and no office within whatever order the Haradrim kept; the notice states that his power there was great and leaves the substance of it undefined. Even the pairing with his companion is left unexplained, so that it cannot be said whether they held anything jointly or were merely two instances of the same case.
The kind of ascendancy available to such a man can be described from the general record even where his own is silent. The Akallabêth relates that the Númenóreans who came to the western and southern shores were held in reverence by the Men who lived there, and that their advantage lay in seamanship, in weapons, in crafts learned in the West, and in lives longer than those of other Men. Power of that order is inherited rather than personal, and it is derivative: it works upon a people not one's own, and it depends on the disparity between them lasting. No weapon, no work of craft, no ring and no sorcery is set beside Herumor's name, and no deed of arms is credited to him.
One nearby possibility is worth naming only in order to close it. The same chapter records that of the nine mortal men who took the Rings of Sauron, three were great lords of Númenórean race; the text draws no line whatever between them and the two men of the far South, and its sentence about Herumor stands apart from its account of the Nine. The limit here is evidentiary rather than a judgement about the man: nothing describes his power being exercised, resisted, inherited or lost, and later notices of the southern peoples proceed without reference to any such lordship. What the record establishes is a position held, not a career conducted from it.
Relationships
The single personal tie preserved for Herumor is Fuinur. The two are brought in together in one breath, share one verb and one fate of record, and nothing sets them apart: no precedence between them, no kinship, no oath, no statement that either preceded the other into the South or drew the other after him. In a body of writing where paired names almost always carry a defined relation — brothers, a king and his heir, a lord and the servant who speaks for him — this pairing carries only likeness of circumstance. Whether they were allies, rivals for the same following, or men who never stood in the same hall and were merely remembered in the same sentence cannot be recovered. Fuinur has no separate notice of his own, so nothing can be borrowed from his side to give the association substance.
The other party to his one attested relation is not a person but a whole people, and that asymmetry is the most telling thing about it. Not a single man of the Harad is named in the records of the Second Age, so the connection cannot be described from below: no predecessor whose place he took, no house that received him, no chieftain who submitted, no tribe or host said to have been his. Even in the fuller annals of the following Age the southern peoples keep their anonymity, appearing as embassies, tribute, banners and captains rather than as named men, from the long enmity with Gondor over the haven of Umbar down to the serpent-standard borne onto the Pelennor. Herumor's counterpart in the record is therefore a collective, and the relation is described only from his side.
Everything else that ordinarily fixes a Númenórean in the web of his kindred is absent. No father or mother is given, no marriage, no house among those whose descents the chroniclers of the island were careful to keep, and no lord above him: the text nowhere attaches him by any word of service, homage or reward to the power that was then gathering the southern lands to itself, though it says plainly enough what that power was doing elsewhere. Nor is any adversary set against him — no captain who opposed him, no kinsman of the Faithful who reproached him. For a race whose histories are largely genealogies, that emptiness is itself a statement: he is entered not as a man with connections but as a position occupied, and the one name beside his own tells us only that the position was held twice.