First-rate

First rate was the designation used by the Royal Navy for its largest ships of the line, equivalent to the 'super-dreadnought' of more recent times. Originating in the Jacobean era with the designation of Ships Royal capable of carrying at least 400 men, the size and establishment of first-rates evolved over the following 250 years to eventually denote ships of the line carrying at least 80 cannons across three gundecks. By end of the eighteenth century, a first-rate routinely carried 100 guns and more than 850 crew, and had a measurement (burthen) tonnage of some 2,000 tons.

The concept of a rating system for English naval vessels dates to the accession of James I of England, following which the fleet was formally divided into "great", "middling" and "lesser" craft. A 1618 commission of enquiry added a further designation of "Ships Royal" for the largest and most prestigious vessels in the fleet, each capable of carrying at least 400 men.

The first Ships Royal - Elizabeth Jonas, Triumph, White Bear, Merhonour, Ark Royal and Victory - were all converted galleons and included three very old vessels that had fought against the Spanish Armada in 1588. Their condition was generally poor, with Elizabeth Jonas and Triumph already completely unserviceable and White Bear so unseaworthy that she was sold for scrap in 1627.

The Navy's rating system was later modified to differentiate ships considered suitable for various functions within the naval tactics of the age of sail. Lower numbers indicated larger and more capable ships. By the mid-18th century ships suitable for the line of battle were first-rate ships carrying at least 100 guns, second-rate ships carrying 84 to 98 guns, and larger third-rate ships carrying 70 to 80 guns. Smaller third-rate ships carrying about 60-64 guns, and fourth-rate ships of around 50 guns, had earlier been considered suitable, but were being phased out. Fifth-rate and sixth-rate ships were frigates usually maneuvering independently of the line of battle.

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