Before we get to the modern-day presidential debates, we'll begin with several important precursors, that helped shape the process we know now.
The Lincoln-Douglas debates of 1858 were a series of 7 debates between two candidates for the U.S. Senate, from Illinois, Stephen Douglas and Abraham Lincoln. While not part of a presidential campaign, these debates are often seen as an early and important example of the type of debate that would eventually become a standard part of the American presidential election cycle. And of course, one of the participants, Lincoln, would become President only a few years later.
The primary topic was the expansion of slavery into new states or territories. Each debate took place in a different city in Illinois. They took the form of long speeches given alternately by each candidate, with each debate being from 2 to 3 hours long. The first one took place in Ottawa, Illinois.
Naturally, we have no audio recordings of the 1858 debates, but all of the speeches were well documented, and have been reenacted on several occasions.
This recording is from a reenactment that was organized and broadcast in 1994 by C-SPAN. The event took place in each of the cities where the debates were originally held. Performed live, outdoors, on a stage built to resemble the one used in 1858. All of the participants, including some of the audience, wore period clothing and acted their parts. The whole thing is really worth a watch. If you're interested, full videos of the event are available here: https://www.c-span.org/series/LincolnDouglas.
Lincoln was portrayed in this debate by Max Daniels, and Douglas by Jim Gayan.
Thanks go to C-SPAN and all of the actors involved.
3 hrs and 4 min