Thankmar

The death of TankmaroThankmar (or Tankmaro, or Tammo) (c. 908 – 28 July 938) was the eldest (and only) son of Henry I of Germany (Henry the Fowler) by his first wife, Hatheburg of Merseburg. His mother had been previously married and widowed, after which she entered a convent. Because she left the convent to marry Henry, her second marriage was considered invalid and the couple split. Thankmar's legitimacy was, therefore, in question.

Henry I then married Matilda of Ringelheim who bore him five more children, four of whom became (or married into) royalty and one (Bruno) who became Archbishop of Cologne: Hedwig, Otto, Gerbega, Henry, and Bruno. In 929, Henry I arranged for his succession and had the arrangement ratified by an assembly at Erfurt, a few year before his death. After his death, his lands and wealth were divided between his four sons: Thankmar, Otto, Henry, and Bruno.

Only Otto, however, was designated by his father to receive the crown, later becoming the Holy Roman Emperor known as Otto the Great. The only succession dispute was between Otto and his younger full brother Henry, who was kept under house arrest in Bavaria during Otto's coronation.

After the death of his cousin, Siegfried, Count of Merseburg (they were related in the maternal line), in 937, Thankmar claimed Merseburg. Otto, however, appointed Gero, Siegfried's brother as successor.