America is the richest nation in the world. Today, The United States has more millionaires and billionaires than any other nation. Americans control over 34% of all the wealth on planet Earth. With a net worth of $86 billion, Bill Gates is the richest person in the world. Gates outranks Spaniard Amancio Ortega Gaona, the #2 richest person in the world, by $16 billion. Six of the ten richest people in the world are Americans and the 10 richest Americans on the planet control $500 billion worth of private wealth. Those 10 billionaires have fortunes ranging from $37 billion (Alice Walton) and $86 billion (Gates). And yet interestingly, despite modern-America's vast wealth and power, the 10 richest Americans are relatively poor compared to their tycoon forefathers.

So, who is the richest American of all time, inflation adjusted? During the peak of the dotcom bubble, Bill Gates briefly had a net worth slightly above $100 billion. That's the same as $136 billion today after adjusting for inflation. That dotcom fortune easily made him the wealthiest person in the world at the time. But how did Gates compare to the wealthy tycoons who came before him? The Carnegies, the Astors, the Huntingtons, the Rockefellers… When you take inflation into account, who was the richest American of all time?

The 40 richest Americans of all time:

#40: James C. Flood – $34 billion (1826-1889, silver mines)

Silver magnate James C. Flood lived from 1826-1889 and had a net worth equivalent to $34 billion in 2012 dollars. One of his mines in Virginia had the biggest mineral strike in US history. Flood also founded the Bank of Nevada.

#39: Mark Zuckerberg – $35 billion (1984 – present, Facebook)

#38: Peter A.B. Widener – $35 billion (1834 – 1915, railway lines in Philadelphia)

Peter AB Widener amassed a fortune equivalent to $35 billion before he died in 1915. Widener built and owned all the railway lines throughout Philadelphia replacing horse drawn carriages and transporting 100 million people a year by 1900.

#37: Collis Potter Huntington – $36 billion (1821 – 1900, railroads)

Central Pacific Railroad magnate Collis Potter Huntington made a fortune connecting the Union Pacific Railroad with the Western US. His work made him the richest man in the world for a time with a 2012 equivalent net worth of $36 billion. Collis' son Henry donated the entire family fortune to charitable causes predominantly in Southern California. California's city of Huntington Beach is named after Henry.

#36: Michael Bloomberg – $36.5 billion (1942 – present, Bloomberg LLP)

#35: George Pullman – $37 billion (1831 – 1897, railway inventions)

George Pullman invented a railway sleeping car which he named after himself the "Pullman Sleeper". This advancement revolutionized railway travel and amassed Pullman a net worth equivalent to $37 billion at the time of his death in 1897.

#34: Alice Walton – $37.1 billion (1949 – present, WalMart)

#33: Jeff Bezos – $38 billion (1964 – present, Amazon)

#32: S. Robson Walton – $38.5 billion (1944 – present, WalMart)

#30: Henry C. Frick – $39.3 billion (1849 – 1919, Carnegie Steel)

Henry Frick was a onetime chaiman of the Carnegie Steel company and an industrialist who helped finance and construct the Pennsylvania Railroad. At the time of his death in 1919 Frick had an equivalent net worth of $39.3 billion. He owned massive amounts of real estate in Pennsylvania and was widely disliked in his time.

#30: Jim Walton – $40 billion (1948 – present, WalMart)

#29: Oliver H Payne – $40.4 billion (1839 – 1917, Standard Oil, US Steel, American Tobacco)

Oliver Payne was one of John D. Rockefeller's partners in Standard Oil and had a net worth equivalent to $40.4 billion.

#28: Christy Walton – $41 billion (1955 – present, WalMart)

#27: JP Morgan – $41.5 billion (1837 – 1913, General Electric, US Steel)

Not only did financier J.P. Morgan single handedly save the US Government during 1895's gold crisis, but he also was critical in the helping launch major corporations like GE and US Steel. The bank which bares his name is still active today.

#26: Henry Huttleston Rogers – $42.6 billion (1840 – 1909, Standard Oil)

Another one of Rockefeller's partners in Standard Oil, Henry Huttleston Rogers also had large investments in railroads and minerals. At the time of his death he had a net worth equivalent to $42.6 billion.

#25: Edward Henry Harriman – $42.7 billion (1848 – 1909, railroads)

After making his first fortune on Wall Street, Edward Henry Harriman used his vast resources to invest in the struggling Union Pacific Railroad. Harriman saved the railroad which made him one of the richest men alive. At the time of his death in 1909 he had the equivalent net worth of $42.7 billion.

#24: John I. Blair – $47 billion (1802 – 1899, railroads)

Like several other men on this list, John I. Blair made his fortune in railroads, most notably the Union Pacific. At the age of 10 he vowed to his mother that he would be rich one day and that turned out to be very true. When Blair died in 1899 he had an net worth equal to $47 billion in 2012 dollars.

#23: Russell Sage – $47 billion (1816 – 1906, railroads)

Russell Sage used success on Wall Street to build up a large stake in smaller railroad companies. When those small companies were bought up by larger conglomerates, Sage made a fortune equal to $47 billion at the time of his death in 1906.

#22: Larry Ellison – $48 billion (1944 – present, Oracle)

#21: Moses Taylor – $48.1 billion (1806 – 1882, banking)

Moses Taylor founded what would eventually become Citibank and helped fund the formation of some of the largest industrial corporations of the time. When Taylor died in 1882 he had amassed a net worth equivalent to $48.1 billion.

#20: William Weightman – $48.1 billion (1813 – 1904, chemicals and land)

William Weightman owned one of the earliest pharmaceutical powerhouses manufacturing the malaria drug quinine sulfate. His company eventually merged into Merck which is still around today. William Weightman net worth was equal to $48.1 billion in today's dollars.

#19: James G. Fair – $49.2 billion (1831 – 1894, silver mining, real estate)

James G. Fair made his first fortune as one of James Flood's partners in a Virginia silver mine then went on to more than triple his net worth through real estate investments in California. At the time of his death in 1894, James G. Fair's net worth was equivalent to $49.2 billion in today's dollars.

#18: David Koch – $50 billion (1940 – present, Koch Industries)

#17: Charlies Koch – $50 billion (1935 – present, Koch Industries)

#16: Andrew W. Mellon – $50.5 billion (1855 – 1937, banking)

Pittsburgh based Andrew W. Mellon made a fortune along with his brother Richard Mellon in finance when the pair helped launch major corporations like Gulf Oil and The Aluminum Company of America. At the time of his death in 1937 Andrew Mellon's net worth was the equivalent of $50.5 billion.

#15: Richard B. Mellon – $50.5 billion (1858 – 1933, banking)

Along with brother Andrew, Richard B. Mellon helped finance some of America's largest early corporations including The American Aluminum Company and Gulf Oil. Pittsburgh based, Richard B. Mellon made many large philanthropic donations with his net worth which was equal to $50.5 billion in 2012 dollars.

#14: Henry Ford – $54 billion (1863 – 1947, Ford Motor Company)

While he did not invent the car, Henry Ford certainly perfected their manufacturing process with his production lines. His Model T was designed to appeal to the masses and was a smash hit. Henry Ford's net worth in today's dollars was $54 billion at the time of his death in 1947.

#13: Sam Walton – $65 billion (1918 – 1992, WalMart)

Walmart founder Sam Walton comes in at #12 on our list of richest Americans with $65 billion. Walton died in 1992 nearly 20 years later each one of his four kids has an individual net worth of over $25 billion. Walmart today is the nation's largest retailer and largest employer with 2.1 million workers and annual revenues of $422 billion.

#12: Marshall Field – $66 billion (1834 – 1906, Marshall Field & Company)

Marshall Field coined the phrase "The customer is always right". He also was the first large retailer to accept exchanges and display prices openly. Field died in 1906 with a relative net worth of $66 billion much of which came from investments in Chicago real estate.

#11: Stephen Van Rensselaer – $68 billion (1764 -1839, land)

Stephen Van Rensselaer was born in 1764 and made his fortune off land. Van Rensselaer received his land as a grant from the Dutch in the earliest days of America. The Dutch gave his family over a million acres of land in New York which he managed until his death in 1839 at which time he had acquired a net worth equivalent to $68 billion in today's money.

#10: Warren Buffett – $70.2 billion (1930 – present, Berkshire Hathaway)

Before he gave most of his fortune away, Warren Buffett's net worth peaked at $64 billion. The Oracle of Omaha made his billions as the Chairman of Berkshire Hathaway, a holding company that owns interests in a wide variety of industries. Berkshire owns GEICO, Fruit of the Loom and hundreds of other investments.

#9: Jay Gould – $71 billion (1836 – 1892, railroads)

Like many other billionaires on this list, Jay Gould made his fortune in railroads. He was also an extremely successful investor and speculator who what one point own more gold than anyone on the planet. When New York's elite refused to allow the unpopular Gould to purchase a private box at the New York Opera he built a much nicer and bigger opera house down the street, The New York Met.

#8: Friedrich Weyerhauser – $80 billion (1834 – 1914, timber, land)

After the Civil War, Friedrich Weyerhauser started a lumber company and eventually went on to acquire over two million acres of land making him one of the biggest private land owners in The US. His timber venture was extremely successful, earning Weyerhauser a personal net worth of over $80 billion in today's dollars.

#7: A.T. Stewart – $90 billion (1803 – 1876, dry goods)

Irish born Alexander Turney Stewart, aka A.T. Stewart, founded the very first department store in New York City which would go on to become the largest retail store in the world for it's time. In 1869 alone Stewart's net worth was estimated at over $1 million and when he died in 1876 his fortune was worth $90 billion in 2012 dollars!

#6: Stephen Girard – $105 billion (1750 – 1831, banker)

Originally from France, Stephen Girard made his fortune in shipping and eventually banking. The oldest person on our list of richest Americans, Girard was born in 1750 and died in 1831. At the time of this death in 1831 Stephen Girard's was the richest man in America with a net worth of $105 billion! He died without heirs so he donated a large portion of his fortune to charity.

#5: John Jacob Astor – $121 billion (1763 – 1848, New York City real estate)

John Jacob Astor made his first fortune by dominating the fur trade in the US. Astor then used his vast financial resources to acquire real estate in New York City including what would eventually become The Waldorf Astoria hotel. Astor was the first multi millionaire ever in America and at the time of his death in 1848 had a net worth equal to $121 billion in today's dollars.

#4: Bill Gates – $136 billion* (1955 – present, Microsoft) *Achieved in 2000

Bill Gates' peak net worth topped $136 billion for a brief moment in 1999 at the highest point of the dot com bubble but has since dropped to $59 billion which still makes him the richest living person in America. Gates has pledged to donate the majority of his wealth to charity.

#3: Cornelius Vanderbilt – $185 billion (1794 – 1877, railroads and shipping)

Cornelius Vanderbilt made an early small fortune running steamboats but didn't come into his vast wealth until he was he invested in railroads at the age of 70. He used his money to start Vanderbilt University and his descendants still own vast real estate in New York City. At the time of his death in 1877 Cornelius Vanderbilt had amassed a net worth of $185 billion in today's dollars.

#2: Andrew Carnegie – $310 billion (1835 – 1919, US Steel)

At the peak of the steel boom Andrew Carnegie invested heavily in steel companies which paid off handsomely. Eventually Carnegie became the head of US Steel which catapulted him to the upper echelons of American wealth. At the time of his death in 1919, Andrew Carnegie was worth the equivalent of $310 billion in today's dollars making him the second richest American to ever live.

#1: John D. Rockefeller – $340 billion (1839 – 1937, Standard Oil)

John D. Rockefeller was not only the richest America who ever lived but also one of the richest human beings in the history of the world with a net worth equivalent to $340 billion in today's dollars when he died in 1937. John D. Rockefeller was the founder of Standard Oil and eventually controlled over 90% of all the oil in The United States. Standard Oil was broken up by the US government for being a monopoly and was eventually broken up into what eventually became Amoco, Chevron Conoco, and ExxonMobil. He was the first American to ever be worth over $1 billion and donated over $500 million to charity upon his death.

What lessons did you learn from this list? Anyone else want to launch a railroad??!!