Genjo and Chitoku were formally recognised as Jun-Meijin, “half-Meijins”, eight-dan pros. They also had an exactly even win record.
Jowa was Meijin and, historically, a Kisei (“Go saint”).
Shuwa had a positive record against Jowa and was the head of the Honinbo house.
Shusaku was unbeaten with Black and, like Jowa, regarded as a Kisei. Also Shuwa’s heir.
Shuho was head of the Honinbo house and had a positive record against Shuei (iirc).
Nakagawa Kamesaburo was a seven-dan professional.
Shuei was head of the Honinbo house and drew in a jubango against Shuho. He was Meijin and acclaimed by Takagawa as the strongest of all classical players.
Shuei didn’t nominate an heir, which suggests that Shusai and Karigane were of quite equal strength.
The Game of the Century was a recognition by Shusai that Go Seigen was an equal opponent.
Fujisawa Kuranosuke was the first modern nine-dan professional.
I think the later individuals can speak for themselves.
Have to put Iyama in the 2010s, he dominated the Japanese Go titles at that point, and would be remembered in the Japanese Go history regardless (even though not necessarily the strongest in the world, and lost most of the international games, since he wasn’t good at shorter time settings).
At Iyama’s peak before 2018, when he still kept all 7 titles, his records against Ke Jie at that point is 3-2, and against Park Jungwan 4-2, and those lost are at late 2017 the point where he started to lose titles in Japan. I think In the mid-2010s Iyama was probably on par with both of them (he is older than both of them, so started to decline earlier is normal). This is measuring past records, not current strength though.
I want to add Rui Naiwei in the 1990s or 2000s to the list, she is the only woman Go player that has beaten Lee Changho at that time, historic record she is 4-5 to him. She just couldn’t find games to compete with male Go players due to prejudice and various political reasons.
Also, her record against Lee Sedol is 2-3, that’s saying a lot. To beat them in the 2000s. And she was already past 30 years old at that point.
I don’t know that much about Gu Li. When I placed him in the 2010s, I was thinking of his 2014 jubango against Lee Sedol (the last big pre-bot event and the subject of the (public-domain) book Relentless).
I disagree that Cho Chikun can be placed as one of the strongest players of the 1970s. Before 1980, he’d won a mere two big titles (Oza '76 and Gosei '79), much less than – for example – Ishida Yoshio. In fact, Ishida should probably be noted in the '70s.
Relevant inclusions by decade (metric: were in the top 3 at some point in that time):
1980s: Kato Masao, Otake Hideo, (they’re listed in the '70s but were still top players in the early '80s) Nie Weiping. (Top Chinese player of the era)
1990s: Ma Xiaochun (Another top Chinese player), Yoo Changhyuk (2nd in the world for a few years behind Lee Changho). Cho Hunhyun was also still a top-3 player.
2000s: Gu Li, Xie He. Cho Hunhyun was also still a top 3 player, which is absurd given that he was pushing 50 at the time.
2010s: Kong Jie, Choi Cheolhan, Shi Yue, Mi Yuting. Of these, only Shi Yue manages to hit #1 on Coulom’s ratings list, but they were all top 3 players at some point. Iyama Yuta made it as high as #4 or so, and would be a reasonable honorable mention as the top Japanese player of the era by far, and a strong competitor internationally. Shin Jinseo should be listed here, as well, becoming the first player to pass 3700 (and in the process take the world #1 spot) in 2018.
Lee Sedol and Gu Li had an infamous rivalry. One reason was that from about 2002 through 2006 (while “Stone Buddha” Lee Changho was seemingly unassailable for more than a decade), Lee Sedol and Gu Li were the most promising players to take Lee Changho down, neck-and-neck in strength, about the same age, and from different nations. They also had complementary fighting styles, which made for flashy and exciting games. But by about 2007, Lee Sedol had emerged as the stronger and succeeded in displacing Lee Changho from the top spot. And by the 2014 jubango, the Lee/Gu rivalry was something of a historical footnote. Lee Sedol dropped only two games and won six in the jubango.
Cho Chikun had a preview of spotlight in the first half of the 1970s. Acording to goratings.org, from 1971 to February 1975, Cho won 20 games and dropped just 4. That includes a 10-game winning streak that featured wins against Fujisawa Hideyuki, Kobayashi Koichi (twice!), Hashimoto Utaro, and Takagawa Kaku. That’s why I included him.
Kobayashi Kochi had his dominating time before Cho Chi Kun, trusting then all the japanese titles.
After 2005 it’s a bit harder to chose between the Chinese players as in my opinion there is like a dozen of almost same top level players, some who won international major tournaments even not mentioned in the lists already given ( I think of Chang Hao in the early 2000’s then Chen YaoYe, Zhou RuiYang…).
I think Cho U could be mentioned too.
