Excerpts from Books and Wikipedia
"Otto I (…), traditionally known as Otto the Great (…), was East Francian king from 936 and Holy Roman Emperor from 962 until his death in 973. He was the oldest son of Henry I the Fowler and Matilda. Otto inherited the Duchy of Saxony and the kingship of the Germans upon his father's death in 936. He continued his father's work of unifying all German tribes into a single kingdom and greatly expanded the king's powers at the expense of the aristocracy." [Wikipedia] "Yet further problems in southern Germany, and with Magyar raids, meant that it was not until 962 that Otto's position was secure enough for him to come to the aid of the Papal States at the request of Pope John XII. . . . He therefore became the first of a line that would last until abolished by Napoleon in 1806." Otto's reign was a time of building many new cathedrals and producing many new illuminated manuscripts. [Furtado: 1001 Days]