Assumption Day commemorates Mary's ascension into heaven at the end of her earthly life. Pope Pius XII defined the Assumption dogma in 1950. King Louis XIII made August 15th a national holiday in 1638
First Marian sanctuary in Western world, built on Esquiline Hill in 434. Named after legend of snowfall on hill where John and wife built church. Originally called "Saint Mary of the Crib" for relic of Nativity crib