The story of the rise of the Rothschild financial empire founded by Mayer Rothschild and continued by his five sons. From humble beginnings the business grows and helps to finance the war against Napoleon, but it's not always easy, especially because of the prejudices against the family.

In Frankfurt, which, in 1780, is part of Prussia, Jews are forbidden to learn trades, to farm or to leave "Jew Street" after sundown. When the tax collector comes to the shrewd money changer Mayer Rothschild and demands 20,000 gulden, a higher tax than the best merchant in the city is charged, Rothschild's son Nathan helps his father trick the collector, who leaves after accepting a 5,000 gulden bribe. However, when Rothschild learns that the man who was to bring him 10,000 gulden from Hamburg has been waylaid and robbed by tax agents, he rages against the plight of the Jews and collapses. On his deathbed, Rothschild advises his five sons that because money sent by coach between countries is often lost, they each should start a banking business in a different country and remain united. He admonishes them to remember the ghetto and tells them that nothing will bring them happiness until their people have equality, respect and dignity. Thirty-two years later, after Napoleon has overrun Europe, Nathan, in London, agrees to a petition brought by Captain Fitzroy, envoy from the Duke of Wellington, to allow his brothers in Vienna, Naples, Paris and Frankfurt to loan money to stop Napoleon. After Napoleon is defeated, Fitzroy and Nathan's daughter Julie plan to marry, and although Nathan would prefer that Julie marry a Jew, he gives his consent because he believes that the world is changing. Wellington, in gratitude, gives Nathan secret information regarding a loan needed by France to recover from the war. Knowing that the loan will make the Rothschilds the most powerful banking house in Europe, Nathan is greatly disturbed when an Allied Council, led by the virulent anti-Semite Count Ledrantz, refuses Nathan's bid even though his is the best and gives the loan to one of his rivals, who, with the representatives of the council, plans to offer a bond to the public to pay for the loan. Furious, Nathan orders Julie to give up Fitzroy and sends her to Frankfurt. After Nathan purchases a previous government bond and drives its cost far below that at which the council members plan to sell theirs, he threatens to offer it to the public at the low cost and thus forces the council members to sell their bond to him. In response, Ledrantz sets off anti-Semitic riots throughout Prussia. Nathan visits Frankfurt, and although he orders the visiting Fitzroy to stay away from Julie, she sneaks out at night and confesses her love. She refuses, however, to marry Fitzroy without her father's consent. When Ledrantz learns that Nathan is in Frankfurt, he issues orders for him to be arrested should he try to leave. After Napoleon escapes from Elba, where he had been imprisoned, the French rally behind him. Ledrantz is then forced to visit Nathan at his home in the Jewish ghetto to persuade him not to grant Napoleon a loan, and he agrees to accept Nathan's terms that the Jews be given the same freedom, respect and dignity as other people have. When Nathan sees Fitzroy, who is about to join Wellington, with Julie, he promises the captain that if he survives the fighting, they can marry. On March 22, 1815, Napoleon reaches Paris. Soon King Louis has fled, and all Europe has become mobilized. In June, after a number of victories by Napoleon, the stock exchange in London goes through a panic, and rumors circulate that it may close. To prevent the closing, which would mean the collapse of English credit, Nathan stubbornly continues to buy amid rumors of Wellington's defeat, until the war ends with Wellington's victory at Waterloo. Sometime later, Julie and Fitzroy are reunited, and Nathan is made a baron by the King of England, who expresses the country's gratitude to this "adopted" son whose generosity and courage brought victory and peace to England.