Book excerpt: This work is concerned with time reckoning and perception in Old Norse culture. Based on an analysis of various prose and poetic works, the author reconstructs the native images of time, as well as their changes in relation to social development, namely the arrival of Christianity and feudalism to the North. The primary sources are divided into three groups. The first group comprises works that contain traces of the original domestic understanding of time, the „Poetic Edda“, „Snorri’s Edda“, legendary and family sagas. The second group includes different types of texts, all of which adopt foreign concepts of time that spread to Iceland especially through various learned treatises and the influence of the Church. Lastly, it is examined how foreign time reckoning and perception affected the temporal structure of kings’ and bishops’ sagas included in the third group of sources.