- 1. admin
- 2. not found
- 3. satoshi
- 4. sirius
- 5. not found
- 6. nandnor
- 7. not found
- 8. not found
- 9. not found
- 10. Xunie
You can check more in the same order, just keep changing the serial number at the end of the URL, for example, to check who was the 30th member who joined the forum, you go: https://bitcointalksearch.org/user/satoshi-30
If you ask about why they joined the forum initially, we can't know the exact reasons, but at that time, most people who joined the forum were interested in Bitcoin and its technology and they mostly were interested in the technical side of it, etc.
Aside from that, I am pleased to learn further through you, as it's always displayed online that Bitcointalk was created on November 22, 2009, but in reality, the admin is stating otherwise. Besides, it's sad that none of the first users of the forum is active anymore save sirius who signed in recently.