Characteristics
Glorfindel was one of the Calaquendi (High Elves) and one of the Noldor, one of the three groups of the Eldar. As his name indicates, he was blond. The Noldor were dark-haired, so this must mean he was related somehow to the Vanyar, Eldar who were blond. His blond hair is considered a mark of his distinction.
Blond hair was also found in the Noldor royal family (House of Finwë), among the descendants of Indis of the Vanyar, second wife of their High King Finwë — namely in the Golden House of Finarfin, his third son, which included Galadriel, who appears in The Lord of the Rings. Both the Vanyar and the Noldor kindreds lived in the fair city of Tirion upon the hill of Túna in Valinor for a time, and in other parts of the royal family tree it has been shown that other Vanyar married in, so it is conceivable that the two groups mingled in more than just the royal line.
We know that he cannot be fully Vanyar for it is stated in The Silmarillion that 'no full Vanyar left Aman' or rather c.f. Turgon's wife Elenwë reached Middle-earth.
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