Can not liberate a city

[StZiza]

I was in a game where I was playing with Austria and Greece and America were my neighbours. In the early stages of the game, Greece took Washington and New York. a few turns after I took Boston (the only city America had left with) and wiped them from game. Quite a few after I decided to liberate Washington from Greece. I captured the city but no Liberate option appeared.

I haven't captured Washington before. Do conquering the civs completely result in not being able to liberate them? What might be the case?

 

[FeiLing]

Thinking maybe that the game still thinks you are at war with them and therefore can't liberate em.
(that would be a bug then I guess).

 

[StZiza]

If we know that the player that conquers the civilization may liberate the civ (when capturing a city they didn't take) yeah, it sounds like a bug.

 

[Nick Hynds]

That cannot be it. I know because I got the option to liberate a Roman city as the Vandals in the fall of Rome Scenario.