It works with every civ you have open borders. You can pillage and sink ships, dodge into the city, get repaired and do harm again. If they follow you, you can still dodge into the city. If you have proved the world is round or play vikings, you have 5 speed, so you can pillage every sea improvement of a city without exposing yourself to attack and it is very probable there's another coastal city 5 tiles away you can enter and repeat this. It is a damn SPOILER!!!