The Royal North American Navy was the naval force of the North American Union. It was modeled on Britain's Royal Navy and operated closely with the older service.

While the RNAN's primary functions were the defence of the NAU and as a coast guard, it was a true deepwater navy with vessels as large as armoured cruisers. Similar to the older service, its ships carried Royal Marines, who provided support in ship-to-ship combat and sent Marines ashore when necessary.

During Colonel Thomas Bushell's hunt to recover the stolen painting The Two Georges in 1995, elements of both the Royal North American Navy and the Royal Marines provided support and assistance for him. Several Marines were killed in a firefight with the Sons of Liberty, allowing Bushell to see that while part of the Navy, the Marines had a distinct pride all their own; the surviving Marines insisted on bringing their fallen back without any direct assistance from Navy personnel.