The formal declaration of the Assumption of Mary, 1950

What the church believed and taught since the beginning was not formally declare until 1950 under the leadership of Pope Pius XII.

Here is the link so you may read the entire declaration, known as Munificentissimus Deus:


http://w2.vatican.va/content/pius-xii/en/apost_constitutions/documents/hf_p-xii_apc_19501101_munificentissimus-deus.html