From the LCMS website:
A leader in Christian Europe in the first half of the 11th century A.D., Bernard is honored in his native France and around the world. Born into a noble family in Burgundy in 1090, Bernard left the affluence of his heritage and entered the monastery of Citeaux at the age of 22. After two years he was sent to start a new monastic house at Clairvaux. His work there was blessed in many ways. The monastery at Clairvaux grew in mission and service, eventually establishing some 68 daughter houses. Bernard is remembered for his charity and political abilities, but especially for his preaching and hymn composition. The hymn texts “O Jesus, King Most Wonderful” and “O Sacred Head, Now Wounded” are part of the heritage of the faith left by Saint Bernard.