The castle games were played in the Shogun's castle by the best Japanese players of the day. The first castle game was in 1626.
In 1664, the castle games became annual (with a few gaps).
1667 is the first year in which more than one game was played.
After 1863, the turmoil of the Meiji Restoration disrupted many Japanese traditional ceremonies and institutions.
John F. I can't see what the Meiji Restoration interfered with in go terms. All the damage was done in Tokugawa times.
Gregory: Of course in this case, I believe the Meiji Restoration interfered in the Castle games before the Shogun by ending the Shoganate.
John F. The castle games ended well before the Meiji Restoration.
Pok: The article at gobase.org is based on my translation of an essay by Masukawa Koichi. I have revised this translation and published it under the title The Castle Games of the Edo Period - An Eye-Witness Report.