Since ancient times, war at sea had been fought much like on land: with melee weapons and bows and arrows, but on floating wooden platforms rather than battlefields. Though the introduction of guns was a significant change, it only slowly changed the dynamics of ship-to-ship combat. The first guns on ships were small wrought-iron pieces mounted on the open decks and in the fighting tops, often requiring only one or two men to handle them. They were designed to injure, kill or simply stun, shock and frighten the enemy prior to boarding. As guns were made more durable to withstand stronger gunpowder charges, they increased their potential to inflict critical damage to the vessel rather than just its crew. Since these guns were much heavier than the earlier anti-personnel weapons, they had to be placed lower in the ships, and fire from gunports, to avoid ships becoming unstable. In Northern Europe the technique of building ships with clinker planking made it difficult to cut ports in the hull; clinker-built (or clench-built) ships had much of their structural strength in the outer hull. The solution was the gradual adoption of carvel-built ships that relied on an internal skeleton structure to bear the weight of the ship. The development of propulsion during the 15th century from single-masted, square-rigged cogs to three-masted carracks with a mix of square and lateen sails made ships nimbler and easier to manoeuvre.
The 16th century saw the development of the man-of-war, a truly ocean-going warship, carrying square-rigged sails that permitted tacking into the wind, and heavily armed with cannon. The adoption of heavy guns necessitated their being mounted lower down than on top of the fore and after castles as previously where anti-personnel weapons had been positioned through the later Middle Ages, due to the possibility of capsizing. This meant that what had earlier been the hold of a ship that could be used either as a merchant ship or warship was now full with cannon and ammunition. Hence ships became specialised as warships, which would lead to a standing fleet instead of one based on placing temporary contracts.
The man-of-war eventually rendered the galley obsolete except for operations close to shore in calm weather. With the development of the sailing man-of-war, and the beginning of the great sailing fleets capable of keeping at sea for long periods together, came the need for a new adaptation of old principles of naval tactics.