https://bitcoin.org domain registration: 2008-08-18 by https://www.namecheap.com, an American company. But using a privacy oriented registrar: https://bitcoin.stackexchange.com/questions/89532/how-did-nakamoto-untraceably-pay-for-registering-bitcoin-org It is unknown how he could have paid anonymously, so it seems likely that the true identity could be obtained by law enforcement if needed.
Bitcoin whitepaper announcement: 2008-10-31 https://www.metzdowd.com/pipermail/cryptography/2008-October/014810.html linking to http://www.bitcoin.org/bitcoin.pdf, email sent from from email@example.com Claimed one year and a half development time. Provider apparently closed in 2014: https://www.reddit.com/r/Bitcoin/comments/3h80mi/vistomailcom_closed_and_domain_changed_owner_in/, as of 2021 just reads:
Once upon a time a man paid me a visit in cyberspace, at this very domain. He planted a seed in our heads that would become the path we are walking today.
Replies in November: https://www.metzdowd.com/pipermail/cryptography/2008-November/thread.html#14863 under firstname.lastname@example.org claims source code shared privately by request at that point.
First open source release: 9 January 2009. Announcement: https://www.metzdowd.com/pipermail/cryptography/2009-January/014994.html "Windows only for now. Open source C++ code is included" Arghhhhhh how can those libertarians use Microsoft Windows??? Had a GUI already.
2011-04-23 Satoshi sent his last email ever, it was to Martti Malmi. https://www.nytimes.com/2015/05/17/business/decoding-the-enigma-of-satoshi-nakamoto-and-the-birth-of-bitcoin.html mentions:
May 2011 was also the last time Satoshi communicated privately with other Bitcoin contributors. In an email that month to Martti Malmi, one of the earliest participants, Satoshi wrote, "I've moved on to other things and probably won't be around in the future."
- Jan 11, 2009 https://twitter.com/halfin/status/1110302988 "Running Bitcoin"