Humans have manufactured and used bladed weapons from the Bronze Age onwards. The sword developed from the dagger when the construction of longer blades became possible, probably in the early 2nd millennium BC. The hilt at first simply allowed a firm grip, and prevented the hand from slipping onto the blade when executing a stab. The 3rd millennium Sumerian bronze "sickle-sword", together with the bronze dagger ranks as a proto-sword

Bronze Age swords with typical leaf-shaped blades first appear in the 2nd millennium BC around the Mediterranean and the Black Sea, and in Mesopotamia.

Iron swords became increasingly common from the late 2nd millennium BC. Iron, stronger and less dense than bronze, has the added advantage of mass-production due to the wider availability of the raw material. The Hittites, the Mycenean Greeks, and the early Celts figured among the early users of iron swords.

Eventually smiths learned that by adding an amount of carbon (added during smelting in the form of charcoal) in the iron, they could produce an improved alloy (now known as steel). Several different methods of swordmaking existed in ancient times, including most famously pattern welding. Over time different methods developed all over the world.

In Pre-Columbian South America and Mesoamerica several cultures made use of sword-like weapons without developing metallurgy; for example swords -- known as "maquahuitl" -- with obsidian "teeth" mounted along the "edges" of a wooden "blade".

During the 17th and 18th centuries, a smallsword became an essential fashion accessory in European countries, and most wealthy men carried one. As the wearing of swords fell out of fashion, canes took their place in a gentleman's wardrobe. Some examples of canes -- those known as swordsticks -- incorporate a concealed blade. The French martial art la canne developed to fight with canes and swordsticks and has now evolved into a sport.

The sword always served more as a weapon of self-defence than for use on the battlefield, and the military importance of swords steadily decreased during the Middle Ages. Even as a personal sidearm, the sword began to lose its pre-eminence in the late 18th century, paralleling the development of reliable handguns.

Swords continued in use, although increasingly limited to military officers and ceremonial uniforms, although most armies retained heavy cavalry until well after World War I. For example, the British Army formally adopted a completely new design of cavalry sword in 1908, almost the last change in British Army weapons before the outbreak of the war. The last units of British heavy cavalry switched to using armoured vehicles as late as 1938. Cavalry charges still occurred as late as World War II during which Japanese and Pacific Islanders also occasionally used swords, but by then an enemy armed with machine guns, barbed wire and armoured vehicles would usually completely outmatch swordsmen.