"It's not to take credit away from some of the later white tours, with Lou Gehrig and Babe Ruth," said Bill Staples, a member of the board of directors with the Nisei Baseball Research Project. "It's just to broaden the understanding that there are more ambassadors who built that bridge."
Baseball Hall of Famer and Negro League legend Biz Mackey and others played in Japan, Korea and Hawaii on the tour, compiling a 35-2-1 record.
Even in modern times, Japan is a whole other world for Westerners, but for the black players on the 1927 tour, it was just so, in a completely different way.
The tour, put together by Japanese-American baseball pioneer Kenichi Zenimura, featured the Los Angeles-based Philadelphia Royal Giants, as well as Zenimura's own Fresno Athletic Club team. The teams toured Japan in the second of three such circuits.
Its effects in the Land of the Rising Sun have been far-reaching -- in 80 years, Japan has gone from a toddling baseball nation to World Baseball Classic champion -- and beyond.
Regarding treatment of Mackey and his teammates, however, Japan was way ahead of its time. Still living in the world of the Negro Leagues and a segregated America, the Royal Giants were treated like, well, royalty. Or sometimes, by royalty.
The emperor of Japan presented a cup to Negro Leaguer and Royal Giant Rap Dixon, quite a step up from life in a country where blacks were treated as second-class citizens.
"When they got over to Japan and Tokyo, they felt a sense of freedom," said Ray Mackey, the grand-nephew of Biz Mackey. "The Japanese people met them more or less with open arms and subsequently caused them to respond in a like manner."
This notion of camaraderie through baseball, an early bond of the sport's modern multiculturalism, is what Sayama's book "Gentle, Black Giants" says helped plant the seeds of pro ball in Japan.
Unlike tours in the 1930s with the big-name Major Leaguers, the Negro League players didn't mock their opponents with hot-dog plays, for example. According to Sayama's book, published in Japanese and still the only book written about the Goodwill Tour of '27, this respect was important to the Japanese players, as was the willingness of players such as Mackey and Frank Duncan to try to teach their gracious hosts about baseball.
"It's not supported with direct evidence [of forming the pro leagues], but he makes a clear contrast between the attitudes of the Major League ballplayers who came later and the African-American players," said Keio University professor Kyoko Yoshida, currently a visiting professor at Brown University who is researching the tour. "The players were so polite, and he talks about how even if one of the Japanese umpires, who sometimes were a bit new, made a mistake, basically [the Royal Giants] would comply."
In another instance, Mackey was beaned on the tour by a young Japanese, who bowed to the burly switch-hitting catcher as a form of apology. Before taking his base, Mackey bowed back.
The tour spanned from March to June, causing the Negro Leaguers involved to miss the beginning of their season.
Regardless of the impact the tour had on the eventual formation of the league, none dispute how it affected diversity in Japanese baseball.
When foreigners first were eligible to join Japanese teams in the 1950s, black players were admitted to the fold early on, largely because of the influence of Japanese Baseball Hall of Famer Shinji Hamazaki.
Hamazaki was a player and a manager in Japan, and one of the most famous pictures from the tour is of Hamazaki and relatively obscure catcher Neil Pullen, but for years, the photo has been widely believed to be just the opposite -- a photo of the iconic Mackey and an anonymous Japanese player.
Even today, posters of the photo can be found on eBay by looking up "Biz Mackey" and "Japan."
In his autobiography, Hamazaki -- who was a manager when the league organized into its current structure -- does not talk at length about the Royal Giants, but he does discuss his commitment to black athletes.
"He got into trouble for hiring these foreign players," Yoshida said. "His owners would tell him to cut them out, and he said, 'If you want to fire them, you want to fire me.'"