There are many important people who changed the course of history, yet some of them unfortunately go unremembered.

Below are 29 little known people who had a profound impact on the world.

1. The vaccine king!

Maurice Hilleman

Of the 14 vaccines routinely recommended in current vaccine schedules, he developed eight: those for measles, mumps, hepatitis A, hepatitis B, chickenpox, meningitis, pneumonia and Haemophilus influenza bacteria.

lula2488

2. Not appreciated in his time.

Ignaz Semmelweis (1818-1865).

He was the physician who came up with the idea of washing your hands before assisting in a birth, because, you know, infections kill moms and babies. He was ridiculed and died in an insane asylum, beaten to death by the guards. Only after his death the existence of germs became generally accepted following the work of Louis Pasteur and others.

Still. There's a big chance many of us are alive now because our great-great grandmothers did not die in childbirth thanks to Semmelweis. He's a true hero of the modern age, and he's basically forgotten.

Little_Morry

3. Great call.

Stanislav Petrov, who made a snap judgement call that averted a nuclear holocaust:

On September 26, 1983, just three weeks after the Soviet military had shot down Korean Air Lines Flight 007, Petrov was the duty officer at the command center for the Oko nuclear early-warning system when the system reported that a missile had been launched from the United States, followed by up to five more. Petrov judged the reports to be a false alarm, and his decision is credited with having prevented an erroneous retaliatory nuclear attack on the United States and its NATO allies that could have resulted in large-scale nuclear war. Investigation later confirmed that the Soviet satellite warning system had indeed malfunctioned.

DeedTheInky

4. Simple, yet effective.

John Bardeen, the inventor of the transistor. The transistor is what allows electronics to process 1's vs 0's, effectively marking the beginning of the digital age.

preposte

5. Quite the resume!

Alhazen

Known as Ptolemy II in Europe during the Renaissance and the smartest man to have lived before Newton came along, he was the founder of geometric optics and used his discovery to estimate the height of earth's atmosphere, discovered that white light was composed of seven colors half a millennium before Newton did, was one of the first analytical geometers and his greatest achievement of them all, was the founder of the scientific method that convinced the world to move on from Greek philosophy to embrace science based on experiment.

Died single.

RexGalilae

6. Charge for your inventions!

John Landis Mason. He invented the Mason jar. Before he invented the rubber seal, home preserves were sealed with wax, which cracked and was unreliable. Contaminated preserves could kill you. Canning was possible but involved expensive heavy equipment. The reliability and reusability of mason jars gained peoples trust and for the first time, anyone could save foods and ship them long distances and eat things out of season. It allowed farmers to sell their entire crop, not just the stuff they could sell before it spoiled. Food became a lot more affordable. Some poor peasant in England could eat peach preserves from Georgia. I know we think of preserved foods as unhealthy but when they first hit the scene in a big way, it vastly improved most peoples diets and nutrition. Cheaper preserved food made long voyages cheaper too, with fewer stops. Traveling became easier and more accessible. The entire world changed very directly from this invention. John Mason sold the patent for a ridiculously low sum and never invented anything else of note. He died broke.

FartHog69

7. That dang Steve Jobs!

Dennis Ritchie. One of the most influential people in software. He was a key person in developing the C programming language and Unix. Every major operating system is largely written in C, and every major operating system apart from Windows is based on Unix.

Anybody who has used a computer in the last forty years owes him thanks, and yet he died a few weeks after Steve Jobs and nobody really noticed.

JimJonesIII

8. Little known heroes.

The Chernobyl Divers. It is truly amazing what happened even though the whole story isn't quite known but they risked their lives to prevent the Chernobyl disaster getting worse and saving possibly millions of lives.

yaxkongisking12

9. No respect!

Howard Florey and Ernst Chain shared the Nobel prize with Alexander Fleming and actually realized the potential of the latter's discovery and produced enough penicillin to test on animals and worked tirelessly to begin to production and use of it to treat people.

"Fleming invented penicillin" is the most common way the story is taught.

Saxon2060

10. A victim of the times.

Lise Meitner, she was the one that came with the insights that made Nuclear Fusion possible (aka the Atom Bomb)

She never got the Nobel prize for it. They discuss whether it was cause of she was a woman, Jewish or both.

As a matter of fact, I can see the place where she got this insight right from my office.

Grogg2000

11. I blame Hitler.

Arminius. He was basically the man who established modern day Europe's north/south divide by driving the Romans out of Germany at the Battle of the Teutoburg Forest in 9A.D.

The main reason he's forgotten about is because Hitler used him as a poster boy to represent "Germanic freedom".

Barseps

12. A real genius actress.

Hedy Lamarr. Remembered somewhat as a glamour-girl actress in the 1930s & '40s, but also helped to invent spread-spectrum and frequency-hopping technologies that are a basis for wifi, CDMA, and Bluetooth. A rare combination of beauty and brains.

MisterBigDude

13. Not cool whatsoever.

I would say Rosalind Franklin. She discovered the double helix structure of DNA and is largely uncredited today, because Watson and Crick didn't give her credit for the work they essentially stole from her.

DontYouCryNoMore

14. A true legend.

Chiune Sugihara He saved around 6000 jews during WWII I believe by writing visas. It was said that he was still writing visas and throwing them out the train window once he was taken away by the Japanese.

Thatguyinabowtie

15. The unsung hero.

The person who decided to stay put and harvest a crop of something year after year.

newsified

16. The Religious hero.

Cyrus the Great, founder of the Achaemenid Persian Empire. One thing that is left out in the very few conversations about Cyrus is that without him there would've arguably been no Jews. So no Judaism, Christianity, or Islam without Cyrus.

Wahpaw

17. I'd take $10k...

Kary Mullis - the inventor of PCR. Think of how many crimes he has helped solve and how many diseases he helped diagnose and understand.

Got a nice little $10k bonus for it.

DrDPants

19. Lots of food thanks to him!

Fritz Haber, discovered the process of synthesizing fertilizer for crops. It's estimated that half the world's total population relies on food grown using his nitrogen method.

fencehoppa

20. Who would've thought!

The lazy guy that drank something that was standing around a long time and found out that letting drinks spoil makes then good for parties.

Lobos1988

21. The Roman savior.

Emperor Aurelian. Ruled for 5 years, and probably extended the life of the Roman Empire by about 200 more. When he took over, in 270 AD, Rome was fighting civil wars in every single one of its territories, there was an army of Goths invading Italy, the Gauls had risen up and taken massive swaths of Europe with them, as had the Palymerenes in the Middle East.

In the 5 years he reigned, he put down every single revolt, reconquered Gaul, Britain, Anatolia, Egypt, and Palestine, put down a major rebellion in Rome itself that would've ended the Empire right there, and reformed the monetary system. In his reign, he was given the title Restitutor Orbis- the Restorer of the World.

Without him, the Dark Ages would have come much sooner, and would probably have been much, much worse.

GunsTheGlorious

22. He started a world war!

Gavrilo Princip, the guy who murdered archduke Franz Ferdinand of Austria in 1914. That incident launched WWI, which led to WWII in the long run. If it wasn't for him, the world we experience today would be a whole lot different.

McWaffeleisen

23. Someone has to lay the foundations.

Charles Babbage, English mathematician and inventor who created several mechanical computers in the mid 19th century. His concepts and these proto-computers laid the foundation for the computing revolution in the 20th century. Alan Turing is now often thought of as the father of the computer, but it would be hard for Turing to do what he did if it weren't for Babbage.

stravadarius

24. He brought down the President.

Frank Wills, the security guard who alerted the police to the break-in at the Watergate Hotel. He was just doing his job and ended up launching the investigation that would eventually bring down the President of the United States, later dying in poverty.

TwilightFanFiction

25. A mathematic hero!

A lot of Middle Eastern mathematicians and scientists from the Islamic Golden Age have been forgotten. During the dark ages, Europe had lost almost all previous knowledge and records, but at the same time in the Arab world, scholars were preserving these texts and doing further studies. Their work has advanced the world forward in many areas of science.

One person is specific is Muhammad ibn Musa al-Khwarizmi who was a Persian mathematician at the time and introduced the modern numbering system to the west. That's why the numeric system is called 'Arabic Numbers'.

x_wonder

26. 'Gravity' ain't got nothing on this.

Michael Collins, third astronaut on the team with Neil Armstrong and Buzz Aldrin. He had to live through several hours of orbit of the moon alone, out of contact with the rest of his team and earth. He was the first human to be so utterly isolated from the rest of humanity, that it was physically impossible to get within 10,000 km, miles of any other human, at all.

Sefera17

27. Unsung heroes.

Jonas Salk. This is the person who created the famous polio vaccine. What made him great was he chose not to patent the vaccine.

Macabalony

28. You bet right.

Abel Wolman. He invented the system for chlorinating drinking water. He has saved more lives than any person in history. And I bet you never heard of him.

Blewedup

29. It isn't like you think.

Charles Martel.

Ask most people why the Crusades were fought and you'll get what they've been fed:

"It was so the Europeans could invade (the holy land) and conquer it."

While that is sort of true for the later crusades, most people forget that enemies were 50 miles outside of Paris in the 9th century. It was an act of defense.

Darth_Poopius