In the early 1800s, King Kamehameha I of Hawai'i made liberal use of foreigners as advisors and counselors. His favorites included John Young, an English boatswain, Francisco Paula de Marin, a Spanish sailor and horticulturalist, John Eliot d'Castro, an English-Portuguese supercargo, and Alexander Adams, a Scottish sailor. Kamehameha gave them land and responsibilities such as military advice, medical attendance, diplomatic contacts, and liquor distilling.
Hawai'i was a country that was only recently exposed to the outside world, and it is understandable that the king would have sought outside knowledge and advice. We should assume that he had in mind the best interests of himself and his nation. Through these foreigners he might have sought to stave off colonization and to profit from trends in trade. Whether his strategy looked good to his compatriots is another matter.
Has any other sovereign installed so many foreigners in such powerful positions?