There were a lot of precedents in both what would now be considered angel and venture investing throughout American history. The founding of the American Research and Development Corporation in 1946 came out of this tradition, but also came out of local and national trends at the time
#Some background on venture capital in America
Venture capital like firms have been around for a long time. For example, much long distance exploration and shipping was organized on this basis, with intermediaries coordinating investors who didn't have any special knowledge in the area to raise capital, hire captains and crews, build ships, and so on. What is probably the earliest form of something resembling venture capital in the United States was also a naval activity: whaling. Once easy picking along coastal waters and the Atlantic were devastated, whaling ships based out of Nantucket and then New Bedford in New England took increasingly long trips to the Pacific. These trips were very risky, but could take in proportionally high returns, quite similar to modern VC returns. They could also be quite long, taking multiple years to return, making supervision difficult. Setting up a trip was also capital intensive: between the ship, captain, and crew, a journey could cost between $20k-$30k in the 1850s (probably in the hundreds of thousands today), a significant sum.
Banks weren't particularly well suited for this type of investment. They preferred to target businesses that would take future loans, and also faced a coordination problem. If a ship took a loan, it might be incentivized to take ridiculous risks to make that money back and more, because any extra money made would be theirs, but if they failed or the ship was lost, the bank would eat the loss. To meet this challenge, agents coordinated investments from wealthy citizens in New England, from industrialists and bankers, but also from people such as doctors and lawyers. Less wealthy could still invest, but for smaller stakes. Agents would then commission a ship, find a captain, and with the captain a crew. Equity would be distributed between the agent, investors, captain and crew, helping to mitigate incentive issues to some degree. Agents would also help with information, collecting logs from ships they sponsor, passing information and advice to new captains the hire. Investors spread their money across many voyages to take advantage of the long tail of success and avoid being wiped out when investments failed. This created a structure remarkably similar to modern venture firms.
As the 19th century wore on, the whaling industry started to decline as whale populations were decimated and alternate sources of fuel and lighting emerged. Investors who were previously heavily invested in whaling diversified in other businesses from railroads to cotton.
These opportunities were available as around New England, as growing cities and towns prospered, an environment of banks and wealthy individuals and families looking to invest grew. The earliest factories looked to venture-ish financing instead of banks for a similar reason as whalers did. At the start of the industrial revolution, Britain sought to protect its lead by banning craftsmen and anyone with knowledge of its technology and factory system from leaving the country. Other countries, such as America, actively sought to steal this technology, and incentivize people to slip out of Britain. But once they were in America, British craftsmen had no capital, and no connections. Early investors struggled with fraudsters who would flee with money and equipment, while immigrants would struggle with investors with wild, impractical ideas and insufficient capital.
The way around this problem was once again attempting to align incentives by giving knowledgeable immigrants significant stakes in companies, while investors capital in increasingly large amounts as the company proved itself. This can be seen in the earliest textile mills in the United States. An Englishman, Samuel Slater, stole textile machine designs by memorizing them, and with experience in a factory, in 1789 disguised himself as a farmer and slipped out of England.
In America, a wealthy merchant family, the Browns, had been attempting to set up a textile factory, to diversify in industries unaffected by vagaries of maritime trade. They had even commissioned the building of a water frame and purchased a spinning jenny. But these were crude, inefficient knockoffs, and without first hand tactic knowledge, they were unable to successfully set up a working factory, and mothballed their machines. Rather than give up, they put out a call through their connections in financial and mercantile worlds that if someone had the appropriate technical skill, they would provide finance and support. Slater, frustrated with the inadequate facilities and support he found in New York, came across this message from the captain of a ship that knew the Browns. Slater moved to Pawtucket, and with the Brown's financial support, set up a functional water frame. They agreed on an a framework of increasingly large payments as Slater proved himself, with the Brown family and Slater both getting 50% of the shares of the company. Given that Slater had no capital, this was a recognition of the value of his skills and knowledge, and of essentially "sweat equity". Though they would eventually split, the partnership was successful, and the first American textile mills were established in Rhode Island and Massachusetts.
Much of the funding of early stage companies in America over the next century and a half would look something like this, though there were of course variations in the structures of the investment styles. As banks were not always equipped or willing to fund new ideas, wealthy families or individuals would do it, providing a mix of angel investing to new firms, venture funding to slightly more established ones, and loans when necessary. As the north industrialized, first in New England, then in Midwest cities such as Pittsburgh and Cleveland, then Detroit and Chicago, fortunes were made in new industry, then reinvested into further corporate concerns. Some investors, such as Andrew Mellon, son of a wealthy Pittsburgh banker, took a very active role in cooperate governance, helping set up professional management, and shunting founders aside when they proved incompetent managers.
The staggering accumulation of wealth in the upper class during and after the age led to families with a massive amount of money at their disposal, and many looked to investing as a way to increase their wealth, and to pass it to their children. Some of them, such as Laurence Rockefeller, This would continue through the world wars, but the Great Depression, World War II, the impact of science and technology on the war, as well as developments in New England would presage the need for greater volumes of capital and different forms of organization.