In Scandinavian history(the state created in 1507, not any predecessor kingdoms), there has only been two Queen regnants.
Victoria I (1547-1564)
Victoria was born in Stolkholm in 1513 as HRM The Princess of Sweden. When she was born, she was second-in-line to the throne after her brother Erik IV(The Prince of Finland). However, the birth of two other brothers quickly placed her in a dismal fourth. In 1542, all of her brothers were assassinated in Lubeck by Kappelist radicals--putting her first-in-line. She succeeded to the throne when her father died in 1547. More to be added.