Here is some history of the 4 x 100 meter world record progression.
The first time the 40 second barrier was broken was in 1936 Berlin Olympics with Jesse Owens, Ralph Metcalfe, Foy Draper, and Frank Wykoff setting a WR in 39.8 seconds.
At the 1956 Melbourne Olympics, the 4x100m WR was 39.5 set by the American team anchored by Bobby Morrow. 39.5 was the standard until the American team lowered it to 39.1 in 1961. That team consisted of Hayes Jones, Francis Budd, Charles Frazier, and Paul Drayton.
Fast forward to 1964, where the USA’s team of Paul Drayton, Gerald Ashworth, Richard Stebbins, and Robert Hayes lowered that time to 39.0 at the Tokyo Olympics
You can see that video here, as Bob Hayes’ anchor leg was the talk of the
day Olympics decade.
4×100 meters vs. 4×110 yards
A little known fact back then was the 4×110 yard relay results were considered for WR ratification because the 4×110 yard is LONGER than the 4×100 meters.
In 1967, the University of Southern California broke the 39 second barrier on the relay distance greater than 4×100 meters. The 38.7 performance was set in altitude at Provo, Utah. That team consisted of Earl McCulloch, Fred Kuller, O. J. Simpson, and Lennox Miller.
Not only was the race in yards (over 2 meters further), but it had a Jamaican as the anchor, making it the last mixed non-National team to hold a WR in the relay.
Of special note is the infamous OJ Simpson, who needs no introduction. (**cough cough see http: slash slash escape cough cough**)
Another interesting piece of trivia is Bill Bowerman’s University of Oregon 4×110 yard relay team with Harry Jerome also tied the existing WR for the relay.
Today, the WR stands at 37.10 set by Jamaica at the Beijing 2008 Olympics.