the northern california ren faire has the goal of re-creating life as it might have been 500 years ago...so each year, it changes time periods by one year...this year it was 1509 that they were attempting to re-create (in some small way)

see for yourself:
http://www.renfair.com/
http://www.renfair.com/socal/
http://www.norcalrenfaire.org/

In 1963, schoolteachers Ronald and Phyllis Patterson originated the Renaissance Pleasure Faire as an outgrowth of school projects.

here is an article containing history, comparisons, etc.
http://en.allexperts.com/e/r/re/renaissance_fair.htm

the Pattersons had established a living history center where staff
and participants worked on authentic costumes, and prepared for the
faire. the people who are involved in the faires have developed a
lingo which includes a lot of huzzah's, m'lord, m'lady, and other
words..Workshops are held the month before the faire -one class is Basics of BFA-Basic Faire Accent Used by participants.

you can see more here:

http://www.myspace.com/renaissancepleasurefaire