Located just below the rose window on the west-facing exterior of the Notre Dame Cathedral is the Gallery of Kings. This is a row of 28 statues portraying the monarchs who ruled over the ancient Kingdom of Judah (its capital was Jerusalem). The monarchs are descendants of Abraham and human ancestors of Mary and Jesus.
While the Notre Dame statues were placed on the church in 1220, the Gallery of Kings was actually installed 1140 to 1250, A.D. on multiple French cathedrals, also including those in Amiens, Reims and Chartres. Note that the number of monarchs varies from 18-56 in these cathedrals depending on the biblical source used, and the Gallery of Kings is only found only on those cathedrals dedicated to Our Lady (Notre Dame). The Gallery of Kings symbolizes Christ’s royal lineage; according to the Bible, Jesus was descendant of Jesse, father of King David.
For centuries, the painted statues quietly blessed the church. However, in 1793, following Marie Antoinette’s beheading during the French Revolution, a mob called for the heads of more royals. The angry crowd mistook the Gallery of Kings for French monarchy and used rope to pull them down from the cathedral exterior. The stone kings were unceremoniously decapitated, and then they disappeared.
What you are actually seeing on the Notre Dame exterior are 19th century replicas. The stone remnants were eventually placed on the streets in 1796 during a clean-up campaign and sold by the government at auction to a building contractor. A strict Catholic, he obeyed church law dictating that any objects or remains removed from a cathedral must be destroyed by burning or burial. Thus, he buried the 21 heads that he had−each measuring about two-and-a-half feet−until they were discovered in 1977 beneath the basement of the French Bank of Foreign Trade in Paris. The heads and other original Notre Dame fragments can be viewed in the Musée de Cluny in Paris.