At the time, the monarch of Silla was Queen Jinseong, who was the third and the last female head of state in Korean history (the other two being: Queen Seondeok of Silla and Jindeok of Silla).
Silla | Queen Seondeok of Silla | Felix Silla | Naemul of Silla | King Seondeok of Silla | Jinseong of Silla | Jinji of Silla | Jinheung of Silla | Beopheung of Silla | Sinmu of Silla | Sinmun of Silla | Seondeok of Silla | Lucio Silla | La Silla Observatory | Jindeok of Silla | Jeonggang of Silla | Ilseong of Silla |
When King Jeonggang was dying in 887, he appointed his sister Jinseong as his heir, justifying the choice of a female monarch by pointing at Seondeok's and Jindeok's successful reigns.