Royal Marines Band Service The Royal Marines (RM) are the marine corps and amphibious infantry of the United Kingdom and, along with the Royal Navy and Royal Fleet Auxiliary, form the Naval Service [2]. They are also the United Kingdom's specialists in mountain warfare and Arctic warfare. A core component of the country's Rapid Deployment Force, the Corps' 3 Commando Brigade is capable of operating independently and is highly trained as a commando force. It can deploy quickly and fight in any terrain in the world. Read more on Last.fm