Over what time period did the dynasty of which Eric Christoffersen of Denmark was a member provide the Kings of Denmark?
House of Estridsen The House of Estridsen, sometimes called the Estridsen or Estrith Dynasty, was the dynasty that provided the Kings of Denmark from 1047 to 1412. The dynasty is named after its ancestor Estrid Svendsdatter. The dynasty is sometimes called the "Ulfinger", after Estrid's husband, Ulf the Earl.
Great Heathen Army The Great Viking Army or Great Danish Army, known by the Anglo-Saxons as the Great Heathen Army (OE: "mycel hæþen here"), was a coalition of Norse warriors, originating from Denmark (and likely also from Sweden and Norway) who came together under a unified command to invade the four Anglo-Saxon kingdoms that constituted England in AD 865.