Zhang Jun (張濬) (died January 20, 904), courtesy name Yuchuan (禹川), was an official of the Chinese dynasty Tang Dynasty, serving as a chancellor during the reigns of Emperor Xizong and Emperor Xizong's brother Emperor Zhaozong. Early in Emperor Zhaozong's reign, Zhang was a major advocate for the imperial campaign to regain power from the regional warlords, but was removed after commanding a disastrous campaign against Li Keyong and forced into retirement. Late in Emperor Zhaozong's reign, with Emperor Zhaozong physically controlled by another warlord, Zhu Quanzhong, who had designs on taking over the throne as emperor (and eventually did, founding Later Liang), Zhu, while formerly an ally of Zhang's, was concerned that Zhang would encourage other warlords into a coordinated campaign against Zhu to stop his takeover, and so had his ally Zhang Quanyi slaughter Zhang Jun and his household. Early life It is not known when Zhang Jun was born. His family was originally from Hejian (河間, in modern Cangzhou, Hebei) and claimed ancestry from Zhang Er (), an ally of Han Dynasty's founder Emperor Gao during the Chu–Han contention, who carried the title of Prince of Zhao in the early Han times, but his traceable ancestry only went back to the Northern Zhou official Zhang Xian (), who was bestowed the Xianbei surname of Chiluo (), but whose son Zhang Zhao () later reverted to the surname of Zhang during Northern Zhou's succeeding dynasty Sui Dynasty. Zhang Zhao's descendants served Sui and Tang Dynasty. Zhang Jun's grandfather Zhang Zhongsu () served as a Zhongshu Sheren, a mid-level official at the legislative bureau of government (中書省, Zhongshu Sheng), but his father Zhang Duo () either did not serve in the imperial government at all, or served in a very minor office. He had at least two younger brothers, Zhang Yong () and Zhang Hang (). It was said that Zhang Jun had an open and careless personally. He studied literature and history extensively, and often spoke in grand terms; because of that latter characteristic, the well-learned did not have good opinions of him. As a result of his poor reputation, he was not initially able to start an official career, and he became a hermit at Mount Jinfeng () and the time studying strategies left by Guiguzi, hoping to use those strategies during troubled times. Early career During Zhang Jun's time as a hermit, he met the eunuch