Empress Kōken, also known as Empress Shōtoku, was the 48th ruler of Japan, reigning from 749 to 758 and again from 764 to 770. She was the daughter of Emperor Shōmu and became the first woman to ascend the throne twice. Her reign is noted for its political intrigue and the influence of powerful court figures, including her lover, Taira no Masakado. During her time, Kōken promoted Buddhism and supported the construction of temples, such as Tōdai-ji. Her rule faced challenges, including conflicts with the Fujiwara clan, which sought to gain power through marriage alliances. Kōken eventually abdicated in favor of her nephew, Emperor Junnin, but later returned to power as Empress Shōtoku.