Long before the world began talking about trillionaires, 110 years ago to be precise, it saw the rise of its first billionaire.
That happened in the United States in 1916, when rising share prices pushed the estimated fortune of oil baron John D Rockefeller beyond $1 billion.
Rockefeller was already one of the richest and most powerful businessmen of America’s Gilded Age. But the billion-dollar milestone came through an unexpected route.
Before Musk, there was Rockefeller
John Davison Rockefeller was born in Richford, New York, in 1839 and grew up near Cleveland, Ohio.
He began his working life as an assistant bookkeeper before establishing a commodities business dealing in hay, grain, meat and other goods in 1859.
As an oil boom spread across neighbouring Pennsylvania, Rockefeller recognised that refining offered more predictable economics than drilling for oil.
He entered the refining business in 1863. Bolstered by his initial success, Rockefeller founded Standard Oil with a group of partners in 1870. By 1965, he established Cleveland’s largest refinery.
Rockefeller was obsessed with reducing costs and known for his ruthless competitive strategies.
Driven by his cost reduction approach, Standard Oil prospered and began to buy out its competitors until it controlled nearly all the refineries in Cleveland.
That fact enabled Standard Oil to acquire pipelines, storage terminals, and negotiate with railroads for favoured rates on its shipments of oil.
It also purchased competing refineries in other cities and vigorously sought to expand its markets in the United States and abroad.
By 1882, Standard Oil had established the first major US business trust and held a near-monopoly over the American oil industry. By the late 1880s, it controlled about 90% of US refining.
The methods used to build that position made Rockefeller one of America’s most admired businessmen and one of its most criticised.
Journalist Ida Tarbell’s investigation into Standard Oil documented the aggressive practices that had allowed it to dominate the industry.
Public hostility towards monopolies eventually caught up with the company.
In 1911, the US Supreme Court ruled that Standard Oil had violated the Sherman Antitrust Act and ordered it to be dismantled. The group was separated into 34 companies: the parent and 33 subsidiaries or successor businesses.
The decision was intended to reduce Standard Oil’s power. It had an unexpected effect on Rockefeller’s fortune.
The breakup that made Rockefeller richer
Rockefeller had retired from the company’s daily operations years earlier, but he remained its largest shareholder.
When Standard Oil was broken apart, his ownership was not confiscated. Instead, he received proportional holdings in the newly independent companies.
Investors soon concluded that the individual pieces were worth more separately than they had been as one regulated and politically vulnerable monopoly.
In 1916, a share of Standard Oil of New Jersey traded at $567. The New York Times calculated that the corresponding shares in the companies created after the breakup were together worth $2,014, more than 20 times the old share’s par value of $100.
The rise pushed the estimated value of Rockefeller’s holdings above $1 billion. The New York Times during the time reported in the papers that the stock-market boom had made Rockefeller a billionaire.
The antitrust order had broken up his company. It had not broken up his wealth.
Several Standard Oil descendants would eventually become some of the largest energy companies in the world, including businesses associated with Exxon, Mobil, Chevron and Amoco.
How large was Rockefeller’s billion?
One billion dollars in 1916 had the purchasing power of roughly $30.5 billion in 2026, based on US consumer-price inflation.
But a simple inflation conversion understates Rockefeller’s economic weight. Forbes has estimated his fortune at about 1.5% of the entire US economy and has ignited debates about income inequality, the concentration of business monopolies and the economic divide at the time.
Musk’s recently bumped net worth of $1.1 trillion has also sparked conversations on income inequality and the widening economic divide prevalent across the globe today.
Notably, Musk’s wealth falls just fractionally short of the International Monetary Fund’s projection of $1.13 trillion for Poland’s entire economic output in 2026.
From Billionaire to Trillionaire: US market leads wealth creation
Rockefeller became a billionaire because the combined market value of his post-breakup shares rose beyond anything previously recorded.
Musk’s journey to becoming a trillionaire was propelled by SpaceX’s historic IPO.
Both fortunes were, and are, largely on paper. A sharp fall in the underlying shares could erase billions or, in Musk’s case, hundreds of billions without any money physically changing hands.
The first billionaire came from oil. The first trillionaire came from rockets, satellites and AI.
The common engine was American capitalism: concentrated corporate ownership, deep capital markets and investors willing to place unprecedented prices on the future.