New Encyclopaedia Britannica has Eadgyth's death date as 946. The generations following Otto's second marriage to Adelaide are too close together to have had Otto marry Adelaide that late. There must be errors in the dates, either Eadgyth died earlier and Otto married Adelaide earlier, or some of the succeeding generations birth and marriage dates were later.
aka Edith (The New Encyclopaedia Britannica. Chicago : Encyclopaedia Britannica Inc., 15th ed., c1987, vol. 9, pg. 2).
Edith was born to the reigning English king Edward the Elder by his second wife, Ælfflæd, and hence was granddaughter of Alfred the Great. Nothing is known of her until in order to seal an alliance between two Saxon kingdoms, her half-brother, King Athelstan of England, sent two of his sisters (Eadgyth and Eadgifu of Wessex) to Germany, instructing the Duke of Saxony (later Otto I, Holy Roman Emperor) to choose whichever one pleased him best. Otto chose Edith and married her in 929. The remaining sister Algiva or Adiva was married to a "king near the Jupiter mountains" (the Alps). The precise identity of the husband of this sister is debated.
In 936 King Henry I of Germany died and his eldest son, Eadgyth's husband, was crowned at Aachen as King Otto I. There is a surviving report of the ceremony by Widukind of Corvey which makes no mention of his wife having been crowned at this point, but according to Thietmar of Merseburg's chronicle Eadgyth was nevertheless anointed as queen, albeit in a separate ceremony. As queen, Eadgyth undertook the usual state duties of "First lady": when she turns up in the records it is generally in connection with gifts to the state's favoured monasteries or memorials to holy women and saints. In this respect she seems to have been more diligent than her now widowed and subsequently sainted mother-in-law Queen Matilda whose own charitable activities only achieve a single recorded mention from the period of Eadgyth's time as queen. There was probably rivalry between the Benedictine Monastery of St Maurice founded at Magdeburg by Otto and Eadgyth in 937, a year after coming to the throne and Matilda's foundation at Quedlinburg Abbey, intended by her as a memorial to her husband, the late King Henry I.
Eadgyth accompanied her husband on his travels, though not during battles. She spent the hostilities of 939 at Lorsch Abbey
Like her brother, Athelstan, Edith was devoted to the cult of Saint Oswald and was instrumental in introducing this cult into Germany after her marriage to the emperor. Her lasting influence may have caused certain monasteries and churches in Saxony to be dedicated to this saint.
Eadgyth's death at a relatively young age, in her early thirties, was unexpected (wikipedia.com)