Last Sovereign, one who ruled the city (7)
I believe the answer is:
nanking
'city' is the definition.
(I know that Nanking is a city)
'last sovereign one who ruled' is the wordplay.
I cannot really understand how this works, but
'sovereign' could be 'king' (king is a kind of sovereign) and 'king' is found within the answer.
'one' could be 'an' (an apple is one apple) and 'an' is located in the answer.
A single letter 'n' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
'the' is the link.
Can you help me to learn more?
(Other definitions for nanking that I've seen before include "Chinese city" , "Eastern city" , "Oriental city" , "Port" .)