The field of emotion research is vast and continuously growing, and laughter might be the most prominent and contagious of all emotions we experience. Even though the word ‘laughter’ can be found in a plethora of study titles, the reader is frequently left disappointed as the focus is most often humour, not laughter. Contrary to popular belief of both scholars and the general public, laughter is not about humour — it is about relationships.

The question of laughter’s role in Íslendingasögur, Íslendingaþættir, and fornaldarsögur — both in terms of its literary function as well as means to convey moral and social conventions to a contemporary audience — takes centre stage in this dissertation. Together, these three corpora contain forty-nine sagas that depict more than one hundred instances of laughing, grinning, and smiling, represented by Old Norse hlæja (to laugh), glotta (to grin), brosa (to smile), and their cognates. Even though this analysis is informed by all of these instances, a selection has been made of the most intriguing and relevant examples to be looked at in close detail; occasionally, other Old Norse genres, as well as continental literature, both secular and religious, are referenced for comparison.

Inspired by recent trends in the history of emotions and neurohistory, the phenomena are introduced from a neuroscientific perspective. This also serves to clearly separate the acts of laughing, grinning and smiling from the concept of humour. Afterwards, the main analysis adopts a binary structure. First, gender differences between laughing men and laughing women are examined. Secondly, the thesis sheds light on laughter in a courtly context by examining various texts in regard to kings and their followers laughing, on the one hand, and provides a detailed study of three Íslendingaþættir and their foolish protagonists, on the other. In addition, instances that are closely linked to Christianity will be discussed. Lastly, laughing, grinning, and smiling non-human and supernatural characters are analysed.

Overall, this thesis demonstrates that the depiction of laughter, smiling and grinning in the analysed genres fulfils several important literary functions: they are deliberate literary instruments to structure the narratives, foreshadow events, indicate hierarchies, and characterise saga characters and through that steer the audiences’ sympathies, to name some. Furthermore, it argues that laughter, smiling and grinning are powerful tools — the depiction of the three phenomena conveys social conventions, morals and attitudes towards certain behavioural practices, to both contemporary and modern audiences. The analysis of these phenomena is a puzzle piece that adds to a better understanding of emotional behaviour in medieval Icelandic narratives and contributes a Scandinavian perspective to the research of emotions in the Middle Ages.