Pope Francis
Pope FrancisUri Lenz/POOL/Flash 90

Pope Francis has declared Mary Elizabeth Hesselblad to be a saint, in recognition of her efforts to save Jewish families from the Holocaust.

Hesselblad was a nurse and served as the mother superior in a Roman convent during World War II. For about six months before the war ended, she hid Jewish families in her convent. Varying accounts suggest that she saved between 12 and 60 people.

In 2004, Yad Vashem added Hesselblad to its list of the Righteous Among the Nations: non-Jews who endangered themselves in order to save Jews during the Holocaust.

The Pope also praised her for her efforts to improve relations between Catholics and other Christians. Hesselblad herself converted from Lutheranism to Catholicism. Swedish Culture Minister Alice Bah-Kuhnke and hundreds of Swedish nationals attended Sunday's ceremony.

Hesselblad died in 1957, at the age of 87. She is only the second saint to ever come from Sweden and the first in over 600 years.