Qiū Chǔjī 丘處機 (1148–1227), zì Tōng mì 通密, hào Cháng chūn zǐ 長春子, was one of the Seven Perfected of Quán zhēn and the single most politically consequential Quán zhēn figure. Founder of the Lóng mén 龍門 branch — the branch that would dominate later Quán zhēn. Most famous for his 1219–1223 overland journey to meet Chinggis Khan at his camp in the Hindu Kush, where the Khan’s favor secured Quán zhēn tax-exemption and lavish patronage across the Mongol empire, positioning Quán zhēn as the dominant Daoist school of the Yuán. Author of KR5e0061 Pán xī jí 磻溪集. The Yellow-Turban-veteran adventure is recounted in his disciple Lǐ Zhìcháng 李志常’s Cháng chūn zhēn rén xī yóu jì 長春真人西遊記.