yes. she was married to Justinian I
Only the year is known - 523
No, and he is in big trouble. In the United States a person can be married to only one person at a time. If they wish to remarry, they must end their present marriage legally, by a court decree. If a...
You can't get married until you have ended your first marriage legally by a court decree.
You get divorced first, unless you are in Saudi Arabia.
You are "married" after the ceremony - once it is done. You are "getting married" beforehand. This is the same as "engaged".