In 1603 all English warships with a complement of fewer than 160 men were known as 'small ships'. In 1625/26 to establish pay rates for officers, a six-tier naval ship rating system was introduced. These small ships were divided into three tiers: fourth-, fifth- and sixth-rates. Up to the end of the 17th century, the number of guns and the complement size were adjusted until the rating system was actually clarified. A 'fourth-rate' was nominally a ship of over thirty guns with a complement of 140 men.

The rating system of the Royal Navy and its predecessors was used by the Royal Navy between the beginning of the 17th century and the middle of the 19th century to categorise sailing warships, initially classing them according to their assigned complement of men, and later according to the number of their carriage-mounted guns. The rating system of the Royal Navy formally came to an end in the late 19th century by declaration of the Admiralty. The main cause behind this declaration focused on new types of gun, the introduction of steam propulsion and the use of iron and steel armour which made rating ships by the number of guns obsolete.