The story goes that a certain princess Ursula agreed to marry a king on the condition that she and her 11,000 devoted virgin followers first be allowed a pilgrimage to the Holy Land. While they set out in that direction they never made it, as they ran into pagan Huns at Cologne who attacked and killed/martyred them all. This wood bust of either St. Ursula or one of her 11,000 companions is one of many that proliferated with reference to the story as popular icons for intercession by those undertaking pilgrimage. The head has been hollowed, so that a skull could be inserted, with the flap to access the skull. See generally.