Short answers, pulled from the story.
The Queen of Sheba is a figure first mentioned in the Hebrew Bible, where she visits King Solomon bearing spices, gold, and precious stones. Her story has since been elaborated in Judaism, Ethiopian Christianity, and Islam, making her one of the few figures shared across all three Abrahamic traditions.
She is called Bilqis in Arabic and Makeda in Geez, the classical language of Ethiopia. The Quran does not name her, referring to her only as a woman ruling the nation of Sheba.
Modern historians and archaeologists identify Sheba as one of the South Arabian kingdoms in what is now Yemen. The ancient city of Marib, whose ruins were found in the Arabian Desert in the 19th century, is identified as the capital of the Sabaean kingdom.
The Kebra Nagast, meaning Glory of the Kings, is the Ethiopian national saga, translated from Arabic in 1322. It names the queen Makeda and describes her visit to Solomon, her conversion, the birth of their son Menelik, and Menelik's later journey to Jerusalem where he was anointed king and returned to Ethiopia with the Ark of the Covenant.
No inscription or artifact directly confirming the Queen of Sheba's existence has been found. Excavations at the Awwam Temple near Marib and the nearby Barran Temple, both associated with her name in folklore, produced no evidence linking them to her. Her historical existence remains disputed among scholars.
The Quran, in chapter twenty-seven, describes the queen as a sun-worshipping ruler of Sheba who receives a letter from Solomon inviting her to submit to God. Rather than going to war, she sends ambassadors with gifts, then visits Solomon herself. She ultimately declares her submission to God after being shown a palace with a glass floor she mistook for water.