For in countries/cities, I always thought it was either "à" (usually for cities, except for a small number of cases e.g. au Canada, au Japon), and "en" for countries.
E.g. J'habite à Melbourne.
J'habite en Australie.
However the above example says j'habite DANS le Yorkshire... how can you live INSIDE a place?
Anna, prepositions are weird things with multiple meanings and idiomatic usages, in both French and English. There is little point in asking ‘why’ - exceptions are rife ! The preposition used depends on the ‘classification’ of the region as you note, the grammatical gender, and in some cases, whether the name commences with a vowel or not.
Yorkshire is neither country nor city and follows ‘the rules for counties etc ’, as per attached lesson :
En/Dans = in/to + regions/states/counties (French Prepositions)
https://www.wordreference.com/fren/dans
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