天安门广场临时指挥部 is the working canonical name in the Free China 1989 archive for the early Beijing–outside-Beijing joint temporary command/execution body active during the martial-law crisis. It is kept strictly separate from later Square command structures.
Documented period
The current controlled crosswalk places this phase from approximately May 19 through May 22, 1989. Zheng Xuguang / 郑旭光 participant materials describe a jointly formed command involving Beijing and outside-Beijing student organizations; the May 21 Wenhui Daily report provides contemporaneous support for a joint elected leadership, identifying Zheng as Director-in-Chief and Lian Shengde / 连胜德 as Deputy Director-in-Chief.
Functions under reconstruction
Evidence and participant accounts connect the command with Square order, security, communications, Beijing–outside-Beijing coordination and efforts to respond to martial-law troop movements. The archive is reconstructing these functions separately so that operational activity is not confused with unlimited political authority.
Organizational relationships
The command followed the formation of 外高联 and involved cooperation with the Beijing student federation represented in the archive as 北高联. Its exact authorization, May 20 representative review, handoff and relationship to later temporary and Square-command structures remain active research questions.
Evidence status
Existence and Zheng–Lian leadership: strongly supported by combined contemporaneous and participant evidence. Exact start hour, mandate, membership, enumerated powers and termination/handoff: still under reconstruction.