Yes, it is. The Gerudo are a race of Hyrule. They just seperate themselves as a band of FEMALE ONLY thieves. They seperate the destert as there OWN province of Hyrule ruled by a lower power, or a duke as some would call it. Same thing with the Zoras and Gorons. The Gorons have a Big Brother known as the duke of that province. The Zora's have a lower king as the duke. The only difference between those and the Gerudos is that the Gerudos or a band of thieves who never sided with Hyrule but are in control of a province of Hyrule. This is evidenced in
TP.
Ordona=Ordonians
Peak=Zora's
Labrynnia=Hylians/ Zora's reside in an area in here because there area is too hostile to therer living conditions.
Eldin=Gorons/ Hylians also live here.
Desert=Gerudo/ Gerudo's have never been sighted in the main region. They either are hiding or are deeper into the envirement
Faron=Kokiri=Kokiri are no where to be found. You can find ruins of past culture of the Koki8ri but the Kokiri seem to live deeper into the forest.