Song Si-yeol (Korean: 송시열, Hanja: 宋時烈, 30 December 1607 - 19 July 1689), also known by his pennamesU-am (우암) and U-jae (우재) or by the honorific Songja (Korean: 송자, Hanja: 宋子), was a Joseon statesman and a Neo-Confucian scholar and philosopher. Born in Okcheon, North Chungcheong, he was known for his concern with the problems of the common people. He served in governmental service for more than fifty years, and his name features over 3,000 times in the Annals of Joseon Dynasty, the greatest frequency that any individual is mentioned. He was executed by the royal court for writing an inflammatory letter to the king. There is a monument to him in his hometown. He is also known as the calligrapher who inscribed an epitaph (Chungyeolmyobi Takboncheop) in dedication of Admiral Yi Sun-sin, which is preserved at the Chungyeolsa Shrine (historical site No. 236).