4th Generation Senso Soshitsu (1622-97) 仙叟 宗室
Sotan's fourth son, Senso, inherited the property containing the Konnichian tea house, where he established the household which later became referred to as the Urasenke. This was during the peaceful and culturally effervescent Genroku period. He served as tea master for Maeda Toshitsune, lord of Kaga (present-day Ishikawa and Toyama Prefectures), and helped to establish a flourishing tea culture in the region. Senso took the potter Chozaemon, a student of the 4th generation in the Raku line, Ichinyu, to Kaga, where Chozaemon established the Ohi kiln to produce tea ceramics. Senso also encouraged Miyazaki Kanchi to establish a foundry to cast tea kettles there.
In the early 1670s, his brothers Sosa and Soshu, heads of Omotesenke and Mushakojisenke, respectively, passed away, leaving him the sole elder of the three families. In that capacity, he held the thirteenth memorial anniversary for his father and the one-hundredth anniversary for Rikyu.