How did Mary die?

Answer 1

The question is not how, but if. Since the early Church, there has been extensive speculation on whether or not the Blessed Virgin died. In the Eastern Churches, it has always been believed that the Blessed Virgin underwent Dormition, that she slept instead of dying. The Western Church has debated the matter. The argument against Mary's death is generally that because she was without sin and its effects (she is the Immaculate Conception), she would not die naturally (neither would Christ have died naturally, but He was crucified). The argument that she did die takes this into account and states that, wishing to be like her Son, she chose to die.

In the mid-1900's, following the devastating Holocaust and numerous other attacks against human dignity, Ven. Pope Pius XII sought to define dogmatically the Assumption of the Blessed Virgin Mary, the long-standing belief of the Church that she was taken directly to heaven, body and soul, as a way of reaffirming human dignity due to God's calling all mankind to heaven. Many theologians looked forward to the proclamation, expecting that the debate would finally be settled. Their expectations were disappointed; the proclamation Munificentissimus Deus (#44) stated "that the Immaculate Mother of God, the ever Virgin Mary, having completed the course of her earthly life, was assumed body and soul into heavenly glory." The formal definition of the dogma of the Assumption gives no answer to the matter of whether Mary died, but avoids it completely by placing it in terms of the end of her life, rather than the moment of her death, dormition, or any other clear terms.

Answer 2

It depends on which Marie you are talking about. There were many "Marie's" who died, so your question is very general and unclear.