(from the FreeBSD Handbook)
The FreeBSD Project had its genesis in the early part of 1993, partially as an outgrowth of the "Unofficial 386BSD Patchkit" by the patchkit's last 3 coordinators: Nate Williams, Rod Grimes and Jordan Hubbard.
The original goal was to produce an intermediate snapshot of 386BSD in order to fix a number of problems with it that the patchkit mechanism just was not capable of solving. 386BSD was Bill Jolitz's operating system, which had been up to that point suffering rather severely from almost a year's worth of neglect. As the patchkit swelled ever more uncomfortably with each passing day, we were in unanimous agreement that something had to be done and decided to assist Bill by providing this interim "cleanup" snapshot. The name for this new project was "FreeBSD", coined by David Greenman.
The first CD-ROM (and general net-wide) distribution was FreeBSD 1.0, released in December of 1993. This was based on the 4.3BSD-Lite ("Net/2") tape from U.C. Berkeley, with many components also provided by 386BSD and the Free Software Foundation. It was a fairly reasonable success for a first offering, and it was followed with the highly successful FreeBSD 1.1 release in May of 1994.
Around this time, some rather unexpected storm clouds formed on the horizon as Novell and U.C. Berkeley settled their long-running lawsuit over the legal status of the Berkeley Net/2 tape. A condition of that settlement was U.C. Berkeley's concession that large parts of Net/2 were "encumbered" code and the property of Novell, who had in turn acquired it from AT&T some time previously. What Berkeley got in return was Novell's "blessing" that the 4.4BSD-Lite release, when it was finally released, would be declared unencumbered and all existing Net/2 users would be strongly encouraged to switch. This included FreeBSD, and the project was given until the end of July 1994 to stop shipping its own Net/2 based product. Under the terms of that agreement, the project was allowed one last release before the deadline, that release being FreeBSD 126.96.36.199.
FreeBSD then set about the arduous task of literally re-inventing itself from a completely new and rather incomplete set of 4.4BSD-Lite bits. It took the project until November of 1994 to make this transition, at which point it released FreeBSD 2.0 to the net and on CD-ROM (in late December). Despite being still more than a little rough around the edges, the release was a significant success and was followed by the more robust and easier to install FreeBSD 2.0.5 release in June of 1995. ...
The long-awaited 5.0-RELEASE was announced on January 19, 2003. The culmination of nearly three years of work, this release started FreeBSD on the path of advanced multiprocessor and application thread support and introduced support for the UltraSPARC and ia64 platforms. This release was followed by 5.1 in June of 2003.
The files here come from one of the mirrors of the FreeBSD repositories.