The German Romantic period(not sure of the actual name) occurred in the mid-1800s and saw a sort of revival of art and stories from the Middle Ages in Europe. The Grimm Brothers and Wagner compiled and presented old folk tales and mythology and brought it into the public eye once more, and as I understand, other mythologies were being explored and popularized at this time as well.
Considering Tolkien, he was a master of literature, language, and mythology and he sought to create his own mythological world. This might be an extension to the works of Hans Christian Andersen who created his own fairytales very much in the style of the Grimm tales.
Is this a correct assumption? They seem quite similar to me but maybe I am ignoring more relevant sources of inspiration.
A few points to consider when mapping out Tolkien's influences:
With all that in mind, it seems wisest to me to say that Tolkien was broadly influenced by early 20th century ancient Germanic studies and related fields, along with the works of authors inspired by the topic of the ancient Germanic peoples and their neighbors. The period you mention above played an important role in the development and history of the field of ancient Germanic studies, but if you're looking for just one person who had the most obvious and direct influence on Tolkien, I'd look closer to Tolkien's home: Morris is probably your man. Hope that helps!
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