李由 / Li You
李由 / Li You enters the wiki through Qinji 129-1 as 李斯’s son and the Qin official defending 荥阳 against 吴广. The source identifies him as governor of 三川 commandery.
Li You’s role in this episode is positional rather than biographical. By holding Yingyang, he blocks Zhang Chu’s western pressure and keeps a strategic route and granary-adjacent military point in Qin hands. Wu Guang’s inability to dislodge him creates the immediate setting for 田臧’s killing of Wu Guang.