Neville Isdell, the chairman of the soft drinks giant, said the firm agreed deals well before it knew where each of the Games would be held. He also said Coca-Cola supported the "credo of the Olympic movement".
Isdell told the BBC: "The sponsorship would have been committed four or five years ahead of that, and don't forget Neville Chamberlain was in Berlin on a very popular mission to talk to Hitler.
"Not everything was known in 1938 and the Olympics were in 1936."
The company, whose Olympic involvement dates back to the 1928 Games in Amsterdam, was also a sponsor for the 1936 Games in Berlin.
Reebok, which is also sponsoring the Games, has already received bad publicity after some of the international legs of the Olympic torch relay suffered violent protests over Chinese rule in Tibet.
The company, which is owned by Adidas, will not allow its athletes to attend press conferences or carry out any one-on-one interviews during the event.
Defending Coca-Cola's involvement in the Games, Isdell said: "What we support is not actually individual governments but the whole aura that surrounds the Olympics and the credo of the Olympic movement.
"We are about the broader context of what the Olympics brings to every country that it takes place in.
"I believe the Olympics are a force for good and if they were not a force for good, we would not sponsor them."
Other big brands associated with the Games include McDonald's, Kodak and VW.