In short answer, none of the notable at least in the primary sources.

 

You may wonder why, but the clue is the understanding of the concept of religion in Early Medieval Europe, especially the Norse ('Vikings' in OP's term) ones (perhaps plural is better) were almost alien to us. it certainly differed from Early Medieval Christianity, but neither of them (Christianity and Norse 'religion') is compatible fully with the our definition of the religion in the 21th century.

• The Norse religions were not uniform, pan-Scandinavian institutional 'religion' during Scandinavian Iron Age (ca. 500-1050). They should instead be considered as a dynamic complex of the rituals and some super natural beliefs, with considerable local differences. Frankly speaking, probably no 'Orthodox' Norse religion(s) as such.
• Generally speaking, the Norsemen (Scandinavian people during the Viking Age) were highly torelant to a minority of the Christians unless they didn't a serious threat against the community, such as the serious opposition against the 'pagan' communal rituals. Some researchers suppose that this religious concept of the Norsemen was rather closer to a 'law', in a sense of the base of the social norms for the community, than individual faith, and I also follow their agrument.
• The Norsemen even were not so hesitant to incorporate a new Jesus as something special into their pantheon (Meulengracht Sørensen 1997: 223). It is well known that we can see clear Christian influences in Edda materials, written in the 13th century Icelandic manuscripts, but the confluence of the Christian elements with the Norse religions in fact began much earlier than their official conversion around the end of the first millennium. To give an example, Steinsland considers the transformation of the representation of Heimdall as a god of the future as a pagan parallel, response to the Christian idea of the God (Steinsland 2005: 227).
• Being a Christian and to 'believe' Norse religions in accordance with contemporary standard was at least OK for the Norsemen. Notker's biography of Louis the Pious of Carolingian Frankish Empire tells us an famous and interesting episode, a story of an Old Dane (Nordmannus) who had come to visit a royal court in Francia more than twenty times spontaneously to get baptized in exchange of fine clothes (Notker Baldus, gesta Karoli Magni imperatoris, II-19). This episode should be understand not as the lack of understandding on Christianity of the Dane, but rather as a testimony of two different concept of the religions that were not mutually exclusive.

From these points I suppose that it was not likely for the Norsemen to force someone to 'convert' to their religion, i.e. to abandon the former faith.

 

These characteristics of Norse religion(s) are much better summarized by /u/Platypuskeeper's comments in How much do we actually know about the ancient religious traditions, deities and narratives of the Norse? than this clumsy comment of mine. If you are interested in this topic, I strongly recommend to read them.

 

+++

Selected References:

• Andrén, Anders. 'Behind "Heathendom": Archaeological Studies of Old Norse Religion'. Scottish Archaeological Journal 27-5 (2005): 105-38.
• Meulengracht Sørensen, Preben. 'Religion, Old and New'. In: The Oxford Illustrated History of the Vikings, ed. Peter Sawyer, pp. 202-24. Oxford: OUP, 1997.
• Steinsland, Gro. Norrøn religion. Oslo: Pax, 2005. (In Norwegian).