August 15 is the Solemnity of the Assumption of Mary, a dogma defined by Pope Pius XII in 1950 proclaiming that Mary, having completed the course of her life, was assumed body and soul into heavenly glory. It “piggybacks” on the dogma of the Immaculate Conception of Mary, proclaimed by Pope Pius IX in 1854, which proclaimed that Mary was conceived without the stain of original sin.