“Heart of Oak” is the official march of the Royal Navy of the United Kingdom. It is also the official march of several Commonwealth navies including the Royal Canadian Navy and the Royal New Zealand Navy. Royal Canadian Sea Cadets sing "Heart of Oak" during days of their parades. (It was also the official march of the Royal Australian Navy, but has now been replaced by the new march, "Royal Australian Navy.") The reference to "freemen not slaves" echoes the refrain ("Britons never will be slaves!") of Rule, Britannia!, written and composed two decades earlier.