It all began with a court case between two manufacturers of reapers. In 1855, the same year the Manny reaper beat the McCormick reaper at the Paris Exposition, Cyrus McCormick filed suit against John Manny for patent infringement [McCormick argued that the Manny reaper was a copy; Manny denied this.] The stakes were enormous: if Manny lost, not only had he to cease production but he would be forced to pay McCormick $400,000 in damages. In 1855, $400,000 was a lot of money.
Both sides lawyered up with the biggest legal names in the 19th century.
Manny’s team was headed up by George Harding of Philadelphia arguably the pre-eminent patent lawyer in the country. Also on Manning’s team was the formidable Edwin Stanton of Pittsburg. Since the trial was to be held out West in Illinois, Harding sought to shore up his team by hiring the best trial lawyer Illinois had to offer, and that proved to be Abraham Lincoln.