Here's a short story:

Pope Saint Gregory I (; c. 540 – 12 March 604), commonly known as Saint Gregory the Great, was Pope of the Catholic Church from 3 September 590 to his death in 604. Gregory is famous for instigating the first recorded large-scale mission from Rome, the Gregorian Mission, to convert a pagan people to Christianity. Gregory is also well known for his writings, which were more prolific than those of any of his predecessors as pope. The epithet Saint Gregory the Dialogist has been attached to him in Eastern Christianity because of his "Dialogues". For this reason, English translations of Eastern texts will sometimes list him as Gregory "Dialogos" or the Latinized equivalent "Dialogus". 

A senator's son and himself the Prefect of Rome at 30, Gregory tried the monastery but soon returned to active public life, ending his life and the century as pope. Although he was the first pope from a monastic background, his prior political experiences may have helped him to be a talented administrator, who successfully established papal supremacy. During his papacy he greatly surpassed with his administration the emperors in improving the welfare of the people of Rome, and successfully challenged the theological views of Patriarch Eutychius of Constantinople before the emperor Tiberius II. Gregory regained papal authority in Spain and France, and sent missionaries to England. The realignment of barbarian allegiance to Rome from their Arian Christian alliances shaped medieval Europe. Gregory saw Franks, Lombards, and Visigoths align with Rome in religion. (End of story)

Provide your best guess for the following question. Give ONLY the guess, no other words or explanation.

For example:

Guess: <most likely guess, as short as possible; not a complete sentence, just the guess!>

Here are a few examples of questions and answers:

Question: When did Pope Saint Gregory die?
Guess: March, 12  604

Question: when was he born?
Guess: 540

Question: what was he known for?
Guess: for instigating the first recorded large-scale mission from Rome

Question: to do what?
Guess: to convert a pagan people to Christianity

Question: Is he knownfor his writings?
Guess: yes

Question: WHat did his father do?
Guess: He was a senator

Question: What type of background did he come from?
Guess: a  monastic one

Question: What did he challenge?
Guess: the theological views of Patriarch Eutychius of Constantinople before the emperor Tiberius II

Question: Who did he send to England?
Guess: missionaries

Question: after he did what?
Guess: regained papal authority in Spain and France

Question: What did he shape in medevil Europe?
Guess: The realignment of barbarian allegiance to Rome from their Christian alliances

Now answer the following question in the same format.

Question: What was he commonly known as?

Saint Gregory the Great