Stonehenge built, quite a major project.
2570 BC -- Great pyramid of Giza completed; another major project. Some records remain of how the work was managed: e.g. there were managers of each of the four faces of the pyramid, responsible for their completion (subproject managers).
208 BC -- the first major construction of the Great Wall of China, one more major project.
1910s The Gantt Chart developed by Henry Laurence Gantt (1861-1919)
1958 The PERT method invented
1969 PMI (Project Management Institute) launched to promote project management profession
1984 The Goal by Eliyahu M. Goldratt published
1997 Critical Chain by Eliyahu M. Goldratt published