Vatnsdæla saga (Icelandic: [ˈvassˌdaiːla ˌsaːɣa]; listen^ⓘ; Old Norse: Vatnsdœla saga) is one of the sagas of Icelanders. The saga follows several generations of a family originating in Norway and settling in the north of Iceland until the arrival of Christianity in the late tenth century.^[1][2]

A fragment of Vatnsdæla saga is preserved in a late-14th or early-15th-century manuscript (AM 445 b 4to).^[3] Complete versions of the text are preserved in later paper manuscripts including AM 559 4to, written between 1686 and 1688, and AM 942 4to, written between 1700 and 1782.^[4][5] These texts likely originate from a 14th-century source, while the saga may have originally been written in the late 13th century.^[6]

Vatnsdæla Saga is essentially a family chronicle. It relates to residents of Vatnsdalur, a valley that runs south from Húnaflói, a large bay in the north of Iceland. The principal protagonist is a man named Ingimundr Þorsteinsson who fought for King Harald Fairhair of Norway at the Battle of Hafrsfjord winning his friendship and an amulet. At the instigation of a sorceress, he moved to Iceland to settle at Vatnsdalur in Húnaþing.