By 1812 the U.S. already had more business corporations than any other country, and possibly more than all other countries put together

From Scale and Scope in Early American Business History: The "Fortune 500" of 1812 by Richard Sylla and Robert E. Wright.  From the Abstract:

Fortune magazine began publishing annual rankings of U.S. corporations by revenue in 1955. Ever since, scholars and forecasters have analyzed changes in the Fortune 500 to help inform their judgments about industry concentration and the relative importance of different sectors of the economy. Unfortunately, earlier data are scarce, especially before the Civil War. Through extensive research we have created a sort of historical "Fortune 500" going back to 1812, ranked by corporate capitalization, which we share here. Numerous insights can be drawn from this dataset, including the historical dominance of the banking and finance sectors and the early importance of manufacturing. Perhaps the larger significance of being able to come up with a Fortune 500 for 1812, though, is the fact that even with a population of only about 7.5 million, U.S. already had more business corporations than any other country, and possibly more than all other countries put together, securing its role as the world's first "corporation nation." The ease of incorporating businesses released a lot of entrepreneurial energy that helped to build an ever-expanding economy and by the end of the 19th century, the U.S. would be the world’s largest national economy with tens of thousands of corporations.