Lý Thánh Tông
Lý Càn Đức (李乾德) was born in the first month of the lunar calendar in 1066 as the first son of the emperor Lý Thánh Tông and his concubine Ỷ Lan. It was said that Lý Thánh Tông was unable to have his own son up to the age of 40, so he paid a visit to Buddhist pagodas all over the country to pray for a child. Therefore, right after the birth, Lý Càn Đức was entitled crown prince of the Lý Dynasty while Lady Ỷ Lan was granted the title Imperial Concubine. To celebrate the event that lifted the emperor's constraint of dying without issue, Lý Thánh Tông changed his era name from Chương Thánh Gia Khánh (彰聖嘉慶) to Long Chương Thiên Tự (龍章天嗣) and gave out a general amnesty for prisoners.