[Numenorean]

Hi Imbey, heres a bit more from Unfinished Tales that might help to explain Gandalfs movements (a bit).
When Gandalf and the other Istari arrived on the shores of Middle Earth around the year 1000 of the Third Age, it is said in U.T (p.390) that "being embodied (as hale old men) the Istari had need to learn much anew by slow experience." For a few centuries they observed and learned rather than interacted and "in that time Men saw them seldom and heeded them little."

As the threat of Sauron and his evil things grew, and presumably once he had gathered sufficient insight and lore, Gandalf "ever went to and fro in the Westlands from Gondor to Angmar, and from Lindon to Lórien, befriending all folk in times of need...thus far and wide he was beloved among all those that were not themselves proud." U.T (p.390-391)

Although he 'journeyed unwearyingly on foot,' "his main province was 'the North,' and within it above all the North-west, Lindon, Eriador, and the Vales of Anduin. His alliance was primarily with Elrond and the northern Dúnedain (Rangers)." U.T (p.398) This seems to indicate that he had more to do with the North after the Kingdom of Arnor fell, perhaps the northern Kings were too proud to deal with Gandalf, as opposed to the comparatively humble Dúnedain Chieftains that followed them?
In the sovereign state of Gondor where the trappings and power of royalty remained intact through the Stewards, even after the last King -Eärnur- died, "Gandalf could do little to guide their proud rulers or to instruct them, and it was only in the decay of their power, when they were enobled by courage and steadfastness in what seemed a losing cause, that he began to be deeply concerned with them."U.T (p.399)