where does the title given to the roman emperor come from?
The title and connection between Emperor and Church continued in the Eastern Roman Empire throughout the medieval period
Holy Roman Emperor
Both the title and connection between Emperor and Church continued in the Eastern Roman Empire throughout the medieval period (in exile during 1204–1261). 
when did henry iv, holy roman emperor ascend to the throne? 1 April 1084 who was his father? Henry III, Holy Roman Emperor was there any controversy during his crowning? UNANSWERABLE which country did he reign over? Germany, Italy, Burgundy was his father in a conflict with any country? Yes, with Bohemia and Hungary who was this king married to? Agnes of Poitou did she act as regent for any monarch? Yes,  Agnes served as regent on behalf of her young son, Henry IV
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Holy Roman Emperor [SEP] Title
For this reason, Charlemagne, the King of the Franks and King of Italy, was crowned Emperor of the Romans ("Imperator Romanorum") by Pope Leo III, as the successor of Constantine VI as Roman Emperor under the concept of "translatio imperii". On his coins, the name and title used by Charlemagne is Karolus Imperator Augustus and in his documents, he used Imperator Augustus Romanum gubernans Imperium ("August Emperor, governing the Roman Empire") and serenissimus Augustus a Deo coronatus, magnus pacificus Imperator Romanorum gubernans Imperium ("most serene Augustus crowned by God, great peaceful emperor governing the empire of the Romans"). The Eastern Empire eventually relented to recognizing Charlemagne and his successors as emperors, but as "Frankish" and "German emperors", at no point referring to them as Roman, a label they reserved for themselves.