I found a farm subsidy database that tracks who gets how much money in farm subsidies. To understand the history of the farm subsidy bill, a reading of the Agricultural Adjustment Act will be necessary. It was originally part of FDR’s New Deal package that was reformulated after it was ruled unconstitutional and then repackaged again during Nixon’s reign because of a wheat deal with Russia. I’ve read a lot about this through the New York Times which recently opened its archives from 1851 to 1980 to the public.