10/04: RAGE ships, John Carmack looks for cool head-mounted display tech, starts tinkering with parts and prototypes.
John Carmack (employee of Id Software, under contractual obligations to ZeniMax) begins discussing head-mounted display tech with Palmer Luckey.
02/22: Carmack publishes a paper on mitigating latency; gives credit to Luckey for providing a Rift prototype
04/15: Palmer Luckey announces that "All of the hardest stuff (Optics, display panels, and interface hardware) is done", announces July 1 Kickstarter date.
5/24: Palmer Luckey signs NDA with ZeniMax (as owner of Id Software), which states that Id will provide "highly confidential and proprietary" information about "proprietary... software, including virtual reality (VR) testbed software and related assets..." (NDA obtained by re/code)
5/29: John Carmack demonstrates the Rift prototype for The Verge
June 2012: Carmack demonstrates early headset prototype at e3 ((here's a partial transcript from the famous Giant Bomb interview/demo.)) Mentions his work on previous prototypes, and that the Rift prototype is the only one working well enough to bring to E3. Mentions using code he developed for Armadillo Aerospace in work with head-tracking sensors, as well as custom sensor firmware he acquired from Hillcrest for his own prototype head-tracking unit (as a bolt-on to the early Rift prototype.) Rift does not appear to include any code; Carmack seems to be doing all output-side programming directly in Doom3 and outputting over VGA.
3/17: ZeniMax pulls the plug on Doom3:BFG edition pack-in
8/7 John Carmack announces role as CTO of Oculus
11/22 John Carmack officially leaves id/ZeniMax
02/3: Carmack tells USA Today that the real reason he left Id/ZeniMax is because of their refusal to participate in the Oculus Rift Kickstarter by releasing the Doom3:BFG edition.