1602: The Founding of Higashi Hongan-ji
Tokugawa Ieyasu granted temple land at Karasuma-Shichijō in Kyoto to Kyōnyo, elder brother of Hongan-ji's chief abbot Junnyo and the former leader of the faction that had advocated fighting to the end during the Ishiyama War, allowing him to establish a new Hongan-ji. This split the institution into the Nishi (West) and Higashi (East) Hongan-ji, a division widely seen as a deliberate move by Ieyasu to weaken the political power of the once-formidable religious organization by dividing it in two.
Events this year
Month 5
Full construction of Nijō Castle began under commissioner Murakoshi Mosuke, with its main buildings prepared ahead of the following year's shogunal appointment.
Month 6
Fushimi Castle, burned during the Sekigahara campaign, was rebuilt as Tokugawa Ieyasu's residence and a center for governing the Kinai region.
Sources 京都市「都市史20 伏見城」
In place of Shimazu Yoshihiro, who had fought for the Western Army at Sekigahara, his successor Shimazu Tadatsune (Iehisa) worked to repair relations with Tokugawa Ieyasu. In Keichō 7, Ieyasu formally recognized Shimazu control over Satsuma, Ōsumi, and territories in Hyūga Province.
Sources 鹿児島県「鹿児島県歴史・美術センター黎明館 常設展示：関ヶ原の戦い」