I've been surprised recently to come across a few serious scholars conflating the Normans and Vikings or using the terms interchangeably. For example, Richard Pipes' Russia Under the Old Regime uses 'Norman' to refer to refer to the Varangians. I don't have the book anymore so I don't have an exact quote, but I believe Felipe Fernandez-Armesto listed Sicily and Antioch as areas of Viking influence as well, which as far as I can tell could only refer to the Norman conquest of Sicily and Bohemond of Taranto.
Is/was this sort of thing common in writing about the Vikings and Normans? And is it accurate history? My understanding had been that, by the time you get toe the various Norman conquests, their connection to the Vikings was pretty tenuous.
I took a look at Pipes' book anyway, and it seems he's generally a bit lax with the demonyms; using not just 'Norse' and 'Norman' interchangably, but also 'Rus' and 'Russians' and even speaks of Russia prior to the founding of Russia or even the Rus' states.
But in any case, while that's confusing it's fairly understandable for a scholar of Russian history since it reflects the Russian usage where both groups are 'Normans' (Норманны). Not least during the Soviet era when certain historians there questioned whether the Rus' had non-Slavic origins. (certainly the Primary Chronicle's account is hardly flattering to Slavs, nor very credible) So at the time Pipes was writing this, there was a 'Normanist' vs 'anti-Normanist' debate ongoing in the USSR, with the latter position being championed by Boris Rybakov. The debate didn't reach far beyond the Soviet borders though and, is pretty dead even there now since the 1990s.
In modern Scandinavian historiography, the term 'viking' is only used for vikingr, that is Scandinavians of the Viking Age who went off on journeys. Historically the term was forgotten entirely after the Viking Age. Then reintroduced to the antiquarians and historians of the 17th century, but did not reach popular fame and general use until the full-blown Viking Romanticism of the 19th century. At which time the English also got a huge interest for those 'noble savages' with whom they had a deep and distant kinship, both directly though invasions and indirectly by being an avatar for the "untamed" Anglo-Saxons who'd once migrated there. And it's basically through that which today's Viking interest stems, from the TV show Vikings to Hagar the Horrible.
Historically Scandianvians had found other people to identify with; such as the Goths (by identifying Goths with Götar/Geats) and Vandals (from Vendsyssel in Denmark). So nationalist Swedish historiography from before the 19th century is referred to as 'Gothicism'. The runes were the 'alphabetum Gothicum', were much older than the Latin alphabet and had been used in ancient times when giants still lived in Scandinava, according to Olaus Magnus.
Where the Swedes saw Goths, the French, on the other hand, saw Normans. In a particularly funny incident some runestones were exhibited by Sweden at the Paris Expo of 1867. On the way back, one of them (the Örby runestone, U1011) fell overboard during reloading in Le Havre, Normandy. This unfortunate incident was soon forgotten though, so that when the stone was found again during dredging of the harbor in 1895, it was instantly hailed as an ancient Norman artwork by local historians until the runologists had their say. Similarly, the runes in the manuscript BnF Grec 375 were conjectured (and later debunked) by the French to be the result of some Norman monk preserving ancient customs. In reality it was written well after the Viking Age (e.g. from the fact that the Yr ᛦ rune has been repurposed to represent 'y', indicating the disappearance of the R sound it had originally) probably around 1241-1245 (after the Tatar invasion of Europe but during Abbot Odo of Saint-Denis), and probably by a Norwegian (given that ᛋ is used for 'c' and ᛍ for 's', in Denmark and Sweden the opposite choice was usual)
I've heard a tour guide in Sicily (Monreale I think) call the Normans 'Vikings' but I don't think that's a rule even there. It's Arab-Norman, not Arab-Viking.
In British historiography the term 'viking' is still often used even in serious contexts for Viking Age Scandinavians in Britain. In that context it's fairly defensible since the Norse 'visitors' weren't from a single country and (even if the English called them all 'Danes' at the time), intermingled and by definition they were of course travelers.
But 'viking' is a pretty powerful marketing term and it's certainly not above even the more serious museumsto use 'vikings' in marketing where they mean Iron Age Scandinavians in general. (Danish National Museum, Swedish History Museum, etc. NB: viking exhibit in Stockholm closed last month for a re-organization and won't open until may 2020. Plan your vacations accordingly)