Today's precision manufactured, high tech water filters are the best that humanity has ever enjoyed up to this point, but they actually do not represent the first effort of humans to provide themselves with clean, drinkable water. Even before microbes had been discovered, people often made conscious efforts to make their water cleaner to drink, usually by boiling.
Of course, the boiling method still survives today as a last resort of those from advanced countries, and the only cleaning method available in many developing nations. It has been both used and neglected throughout history, which makes the many examples of people dying from failing to boil their water all the more appalling, since the process was known to produce safe, potable water at least since antiquity.
The Greek physician Hippocrates, who lived over three hundred years before Christ, wrote down boiling water and filtering it through cloth as a way to improve its flavor and usefulness. Of course, filtering through cloth will reduce sand, silt, debris, and macroscopic creatures like wrigglers or water beetles, but it does nothing to prevent bacteria and protozoa from remaining in the water. Still, the Greek's double treatment probably saved many lives.
It is possible, however, that Hippocrates was drawing on Ancient Egyptian knowledge at least a thousand years older. Pharaoh Amenhotep II's tomb appears to show a large water filtration system consisting of many small jars and siphons mounted in a wooden frame, though the exact workings are unclear, and the Egyptians likely also knew to boil and strain water.
In ancient India at about the same time as Hippocrates, a physician named Sushruta also realized that pouring boiling water through layers of sand and gravel would clean it – a viable technique of filtration, though no longer necessary thanks to our sophisticated modern filters.
Water filtration only became a concern again in the 17th century and advanced rapid thereafter. Modern gravity feed water filters were first created in the 19th century because of the needs of the British Empire for clean water that could be drunk without English soldiers and administrators risking tropical diseases to which they had no resistance.
In fact, British Berkefeld – Berkey – filters are the direct descendants of these highly practical devices. Their “Imperial” and “Crown” Berkey filters are named for these early days when the empire was assisted, in part, by the ability to provide clean, safe water to its troops.
The technological and population explosion of the late 19th and early 20th centuries went hand in hand to create the flowering of scientifically designed water filters that we see today. With huge quantities of sewage and poisonous industrial chemicals everywhere, water quality became an extremely urgent matter and remains so today. Water filters have played an important role throughout history, but today they are one of the many elements vital to keeping our complex civilization functioning.