As a history major I am often questioned about the validity and the usefulness of such a study. I could talk about the wars, politics, or even the societies that seemed to get it right and prosper, however; it is diseases and epidemics that truly impact societies the most. If one were to take the casualties of all wars in human history they would pale in comparison to those killed be disease. While many claim that science, war, or globalization has shaped human society the most. The most profound moments in human history are due to the invisible killers we know today as diseases.

One of the greatest examples would be the infamous Black Death. The disease later known as Yersinia Pestis would go on to kill millions, yet it would also create the greatest triumphs of human rights. Before the deadly pathogen destroyed almost one third of Europe, although some estimates put it closer to fifty percent, a majority of the population lived in conditions that were abysmal. After almost thirty, if not closer to fifty, percent of the population was wiped out by the disease the peasants became much more powerful. The sheer lack of people allowed for previously oppressed peasants to simply purchase new land and become the masters of their own destiny. This empowered many, allowing for them to break the cycle of economic and social depression created by a class of people that claimed power through an unseen god. Through an ironic twist a similar unseen force unseated them. The effects of this would later lead to a greater awareness of the rights of all humans and the limits of power that monarchs and those in power were restricted by.

After the huge impact that population loss had on the world many strived to prevent such a massive loss of human life. Scientist such as Sammelwies and John Snow would work tirelessly to prevent history from repeating itself. It was in the 20^th century that possibly one of the greatest achievements of man was carried out. In 1980 the world declared smallpox an eradicated disease, only existing in a select few locations. The possibility of a natural form of infection was eliminated and the world seemed to be united in an amazing effort to break down the barriers of nature. While flight, space travel, and the internet were achieved in the same century, all pale in comparison to the eradication of smallpox. The simple matter of the event from a historical context is that eradicating the disease saved millions of lives. For comparison about 8.2 million people died of cancer in 2012 alone, small pox would kill about 3 million per year in the 20^th century alone. The lack of smallpox in the world today would be almost comparable to curing cancer by mortality standards. This victory of man against nature is one that is monumental in principle. Mankind was able to willingly abolish a deadly organism by sheer volition and unprecedented cooperation.

When man had conquered one disease the future looked hopeful. If one of the most deadly diseases known to man was able to be defeated then how could similar diseases pose a threat? The HIV epidemic of the 70’s and 80’s awakened a new breed of social problems. The disease, while it did kill millions, was not as rampant in populations such as the black death and small pox. It was the stigma attached to it the disease that created a huge impact on societal norms and political life. It was originally thought to be a disease that only affected homosexual men, quickly becoming a focal point of religious organizations that opposed gay rights. The lethality of the disease turned into evidence of divine judgment for transgressions against the bible, equivalent to the arguments created by the church as a cause of the black death. Like many illnesses HIV only provided the ability to marginalize a minority group even more. While the social isolation of those afflicted by the disease was great, the lack of medical support was a deadly side effect. Doctors often refused to see patients for fear of contracting the deadly illness. The lack of information led children infected with the disease due to tainted donor blood to be excluded from school and isolated. The president only fueled the flames of ignorance when he chose to ignore and condone the ignorant actions of a misinformed public.

It is these examples, along with many others, that create the rich history of mankind’s coexistence with microorganisms. While these organisms are invisible to the naked eye, they have shaped almost every aspect of human history. Microorganisms have stopped invincible armies such as napoleon whose men became ill after crossing rivers in the brutal winters of Russia. They have crushed empires such as the Athenians who suffered defeat in the Peloponnesian war due to an outbreak of diseases. It is truly awe inspiring impact these organisms have on history that is often overlooked. Many choose to ignore the fact that every war, nation, and scientific discovery has been influenced in some way by the impact of these unseen organisms have on mankind.