Which preposition to use with capitano

of Occurrences 2%

This morning, the General and myself went to pay our respects to the Gran Capitano of the Holy League, and we left our cards.

in Occurrences 1%

" "Under what name and circumstances was he known to you, Signore?" "Ehhe called himself Sir Smees, a capitano in the service of the English king.

Which preposition to use with  capitano