I am currently watching the show 'Ragnarok' on Netflix and it seems to me that their image of Thor & Loki is also heavily borrowed from the looks popularised by the MCU movies - i.e. Thor being big and stupid with long hair (usually blonde) while Loki is thin and tall with black hair. I tried to Google depictions of Thor & Loki and only found paintings from the 1800's which would have been heavily influenced by Christian thoughts.
Are there any original surviving depictions of Thor & Loki? Did they always look like this? I tried to search in AskHistorians sub but couldn't find anything.
Put it simply, we don't have almost any reliable iconographical sources of Old Norse deities like Þórr and Loki prior to the conversion mainly due to the dearth of written letters except for runic alphabet in pre-Christian Scandinavia. In short, there are some illustrations (or, carving) identified as deities or some famous heroes like Sigurðr the Dragon slayer by modern scholars, based on the depicted scene and its apparent correspondence to the extant written texts as well as some famous 'attribute' like Þórr's hammer, but virtually all of such illustrations lacks the annotation to confirm this kind of identification.
There are at least also some illustrations found in Icelandic manuscripts, but almost all of them were depicted in post-reformation Early Modern Period, long, long after the conversion of Iceland.
Anyway, the following is the well-known and relatively less disputed illustrations and statues, customarily identified with Þórr and Loki.
On the other hand, from Scandinavian Peninsula, a few scholars had interpreted the central one of three crowned figures embroidered in so-called Skog Tapestry (Skogbonaden), from 12th or 13th century as three Old Norse deities, Óðinn, Þórr and Freyr, but alternative hypotheses like three historical kings or even three biblical magi seem to have got more popular now at least in Scandinavia.
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