Spouses and children:

Married in 940, Lüneburg, Niedersachsen, Tyskland, to Oda av SACHSEN 920-973 with
F Mathilde av BILLUNG 945-1008
M Bernhard av BILLUNG 950-1011
F Suanhilde av BILLUNG 952-1014

Married to Hildegarde av WESTERBURG

Hermann is generally counted as the first Billung duke (Herzog) of Saxony, but his exact position is unclear. The ducal Ottonian dynasty had risen to German royalty with the accession of Henry the Fowler in 919 and had to concentrate on countrywide affairs. At least in 961, when King Otto I of Germany marched against the Kingdom of Italy for the second time, he made Hermann the administrator (procurator regis) in his Saxon lands.

When in 936 King Otto I had ascended the throne, he appointed Hermann a margrave (princeps militiae), granting him the Saxon march north of the Elbe river. His Billung March stretched from the Limes Saxoniae in the west along the Baltic coast to the Peene River in the east, roughly corresponding with the later Mecklenburg region. Otto thereby disregarded the claims of Hermann's elder brother Count Wichmann, a brother-in-law of Queen Dowager Matilda. Wichmann in turn joined the unsuccessful rebellion of King Otto's half-brother Thankmar and Duke Eberhard of Franconia in 938. Having more autonomy than the contemporary margrave Gero ruling over the adjacent Marca Geronis in the south, Hermann exacted tribute from the local Polabian Slavs of the Obotrite tribal federation.

Upon his brother's death in 944, he also became count in the Saxon Bardengau around the town of Lüneburg, where he founded the monastery of St Michael in that city. He again disregarded the inheritance claims raised by his nephews Wichmann the Younger and Egbert the One-Eyed. In 953 both joined the countrywide rebellion started by King Otto's younger brother Duke Liudolf of Swabia, which only collapsed due to the massive invasion of Hungarian forces. During this grave crisis, the king, who was also Duke of Saxony, began entrusting more and more of his authority in the Saxon lands to Hermann during his absences. However, Hermann was never named dux in royal documents. Instead, he is named as a military leader, count, and margrave.

His position was solidified, when on 2 February 962 King Otto was crowned Holy Roman Emperor in Rome by Pope John XII. Hermann was received like a king by Archbishop Adalbert of Magdeburg in 972, which even annoyed the emperor. He may have been the founder of the Hermannsburg locality in the Lüneburg Heath, first mentioned in 1059.

Gift med
Oda av Sachsen, född 920 i Niedersachsen, Tyskland, död 973-03-15 i Quedlinburg, Sachsen-Anhalt, Tyskland. Grevinna av Bardengau-Lüneburg. Buried - St. Mikaelskyrkan, Lüneburg, Niedersachsen, Tyskland.

Barn:
Mathilde av Billung, född 945, död 1008-05-25
Bernhard av Billung, född 950, död 1011-02-09