 In 1803 the Swedish inventor John Ericsson is born. After a military career he went to England and became one of the first builders of locomotives. Despite large debts, he invents the propeller. In 1839 he crosses the Atlantic and builds ships for the US Navy. When the US civil war breaks out, the Federation needs a ship to match the Confederate  Merrimac  and preventing them from exporting cotton to Europe. Ericsson builds the  Monitor , a ship the Federation needs to win the war.