Commodore (Royal Navy) Commodore (Royal Navy) Commodore (Cdre) is a rank of the Royal Navy above captain and below rear admiral. It has a NATO ranking code of OF-6. The rank is equivalent to brigadier in the British Army and Royal Marines and to air commodore in the Royal Air Force. The rank of commodore was introduced during the 17th century in November 1674 (though not legally established until 1806). In 1684 the navy introduced two classes of commodore, the first known as a "Commodore Distinction" and the other a "Commodore Ordinary"; these would later evolve into commodores first and second class. In
Lieutenant (British Army and Royal Marines) Lieutenant (British Army and Royal Marines) Lieutenant (; Lt) is a junior officer rank in the British Army and Royal Marines. It ranks above second lieutenant and below captain and has a NATO ranking code of OF-1 and it is the senior subaltern rank. Unlike some armed forces which use first lieutenant, the British rank is simply lieutenant, with no ordinal attached. The rank is equivalent to that of a flying officer in the Royal Air Force (RAF). Although formerly considered senior to a Royal Navy (RN) sub-lieutenant, the British Army and Royal Navy ranks of lieutenant and sub-lieutenant are