Listen to Iolanthe: Act II. No III. When Britain Really Ruled the Waves online. Iolanthe: Act II. No III. When Britain Really Ruled the Waves is an English language song and is sung by Pro Arte Orchestra, Sir Malcolm Sargent and Glynbourne Festival Chorus. Iolanthe: Act II. No III. When Britain Really Ruled the Waves, from the album Gilbert & Sullivan Favourites, was released in the year 2012. The duration of the song is 3:02. Download English songs online from JioSaavn.