In Norse mythology, Sumarr (Old Norse "Summer") and Vetr (Old Norse "Winter") are personified seasons. Sumarr and Vetr, personified, are attested in the Poetic Edda, compiled in the 13th century from earlier traditional sources, and the Prose Edda, written in the 13th century by Snorri Sturluson. In both, the two are given genealogies, while in the Prose Edda the two figure into a number of kennings used by various skalds.