Himyar

Himyar was a polity in the southern highlands of Yemen, as well as the name of the region which it claimed. Until 110 BCE, it was integrated into the Qatabanian kingdom; afterward, it was recognized as an independent kingdom. According to classical sources, their capital was the ancient city of Zafar, relatively near the modern-day city of Sanaa. Himyarite power eventually shifted to Sanaa as the population increased in the fifth century. After the establishment of their kingdom, it was ruled by kings from the dhū-Raydān tribe. The kingdom was named Raydān.

tribal war in 5th and 6th-century Arabia

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Raḥmānān (Musnad: 𐩧𐩢𐩣𐩬𐩬 rḥmnn, "the Merciful") was an epithet and theonym predominantly used to refer to a singular, monotheistic God from the fourth to sixth centuries in South Arabia (though the term originates much earlier in Syria), beginning when the ruling class of the Himyarite Kingdom converted to Judaism and replacing invocations to polytheistic religions. The term may have also been monolatrous until the arrival of Christianity in the mid-sixth century.