A few steps to date in the GMPG history are as follows:
1992
The GMPG was first mentioned by Neal Stephenson in chapter 3 of his book Snow Crash.
2003 March
The Founders (Tantek Çelik, Eric Meyer, Matthew Mullenweg) met at the SXSW conference in Austin TX USA. Inspired by blogs and blogrolls, they decided they wanted a simple way to express human relationships on the Web, and developed the initial principles for XFN, the XHTML Friends Network.
2003 May
First draft of XFN and various satellite documents were written, including XMDP, a general format for XHTML Meta Data Profiles in XHTML.
2003 August
The Founders decided to create a site to house such protocols/formats and GMPG.org was born. Amongst a flurry of activity numerous documents were written and posted.
2003 September
The Founders finally find enough spare vacation and other off hour moments to polish GMPG.org, XFN and related documents enough for a limited preview.
2003 December
After a bunch of minor tweaks in off hours and last minute comments from previewers, XFN is released to the public.
2004 August
GMPG releases XFN 1.1 with three new values ("contact", "kin", and "me") as a poster at Hypertext 2004 in Santa Cruz, California (USA), the Fifteenth ACM Conference on Hypertext and Hypermedia.