Dumbledore, even if in spirit or through some magical means, could be an ally. His wisdom and foresight could guide Harry in making important decisions for the kingdom. Also, the house - elves, if Harry treats them fairly and gives them freedom and a place in the kingdom, could be loyal allies. They could take care of the day - to - day running of the castle or important buildings in the kingdom, using their unique magical abilities.
His friends Hermione and Ron would most likely be his allies. They have been with him through thick and thin in the original series.
One possible plot could be that Harry, after defeating Voldemort, decides to create a kingdom where magic and non - magic folk can live together in harmony. He uses his knowledge of magic and the respect he has gained to build a new society with its own set of laws and governance that are fair to all. For example, he could create schools that teach both magic and Muggle subjects to promote understanding between the two worlds.
Ron could also be a great ally. His loyalty and courage would be important. He might be in charge of security, using his skills in wizard chess to plan out defensive strategies. And of course, the Weasley family in general could offer a lot of support, with their various skills and connections in the wizarding world.
Hermione and Ron would surely be his top allies. Hermione with her vast knowledge of magic and Ron with his loyalty and combat skills. They've been with Harry through thick and thin. Also, the members of the Order of the Phoenix like Sirius Black (if he's still alive in the fanfiction), Lupin, and Moody could be great allies. They have experience and are very powerful wizards.
Hermione would definitely be one of his top allies. Her intelligence and knowledge of magic and history would be invaluable in helping Harry rule. She could advise him on laws and policies, especially those related to education and the treatment of non - human magical beings. Ron would also be an ally. His loyalty and his understanding of the wizarding world's less - sophisticated side could help Harry connect with the common wizards.
Hermione would definitely be one of his allies. She is smart and resourceful and would be able to help Harry navigate the new political and magical situations he faces as a prince. For example, she could research ancient laws and prophecies related to his new status.
Ron could also be an important ally. His loyalty and courage would be great assets. He might be in charge of security or diplomatic relations with other magical communities, using his Weasley charm to smooth things over.
Hermione would surely be one of his allies. With her vast knowledge of magic, she could help Harry understand and adapt the magic of Skyrim. Also, Ron could be there, providing his loyalty and his own brand of wizarding skills. In Skyrim, characters like the Companions might side with Harry. They would be attracted to his leadership and the new ideas he brings with his wizarding background.
Perhaps some of the magical creatures that Harry has befriended over the years, like the centaurs or the house - elves, could become his allies. They could offer their unique skills and knowledge to help Harry in his new role, and Harry, in turn, could work towards better rights and treatment for them in the wizarding world.
It could be some of the pure - blood supremacist families who don't want a half - blood like Harry to rule. They might try to undermine his authority at every step.