The same goes for "King," "Queen," "Count," "Countess," and any titles: if they are placed together with a proper noun, they should be capitalized ("King Edward II," "Emperor Elagabalus") but if not placed together with a proper noun, they should not be capitalized ("the king led his army into battle," "the emperor was ...
Do you Capitalise king and queen?
It's 'Queen Elizabeth,' she's the 'queen': "Capitalize king, queen, prince and princess when they are used directly before one or more names; lowercase when they stand alone," AP Stylebook says. ... Capitalize a longer form of the sovereign's title when its use is appropriate or in a quote: Her Majesty Queen Elizabeth."
Does King need a capital?
However, if you want to show more respect for, say, the king, then it can be written with a capital letter: King. A lot of job titles in Dutch companies are English and, in English speaking countries, the first letters would always be written in capitals.