Starting in 1993 and ending in 1996

Important events

- Royce Grace and Ken Shamrock compete in UFC 1

- Dan Severn debuts at UFC 4

- Tank Abbott makes his debut at UFC 6

- Mark Colman make his debut at UFC 10

Starting in 1996 and ending 1999

Important events

- Debuts of Joe Rogan and Victor Belford at UFC 12

- Tito Ortiz and Randy Couture make their Debuts at UFC 13

- Debut of Pat Miletich at UFC 16

- Dan Henderson, Carlos Newton, and Jeremy Horn make their debuts at UFC 17 ( Chuck Liddell makes debut un televised)

- Debut of Bas Rutten and Evan Tanner at UFC 18

- Second appearance of Wanderlei Silvia during UFC 20, first appearance came at Ultimate Brazil

Starting in 1999 and ending in 2001
Important events

- Matt Hughes and Jens Pulver debut ( Pulver un televised) at UFC 22

- Debut of Shonie Carter and Ian Freeman at UFC 24

- Murlio Bustmante debuts at UFC 25

- Debut of Andre Arlovski, Renato“Babalu”Sobral, Josh Barnett, Gen Mc Gee at UFC 28

- Matt Lindland debuts at UFC 29

- Sean Sherk, Elvis Sinosic, Phil Baroni debut at UFC 30

- Tito Ortiz wins Middleweight Championship at UFC 30

Starting in 2001 ending in 2002

Important Events

- BJ Penn and Matt Serra debuts at UFC 31

- Yves Edwards debuts at UFC 33

- Frank Mir debuts at UFC 34

- Matt Hughes Wins Welterweight belt at UFC 34

- Jens Pulver vs. BJ Penn for Lightweight Championships at UFC 35

- At UFC 37, Ivan Salaverry and Robbie Lawler debuted

Starting in 2002 ending in 2006

Important Events

-Tim Sylia debuts at UFC 39

-UFC 40 Tito Ortiz vs. Ken Shamrock

- Rich Clementi, debuts at UFC 41

- Rich Franklin, Hermes Franca, David Louisseau, and Duane Ludwig make debuts at UFC 42

- UFC 43 Chuck Liddell vs. Randy Couture

- Edwin Dewees, Karo Parisyan, and Nick Diaz debut at UFC 44

- George St Pierre debuts at UFC 46

- UFC 47 Tito Ortiz vs. Chuck Liddell

- Jay Hieron debuts at UFC 48

- Joe Riggs debuts at UFC 49

- UFC 50 Matt Hughes vs. George St Pierre

- Patrick Cote debuts at UFC 50

- Paul Buentello, James Irvin debut at UFC 51

- UFC 52 Liddell vs. Couture 2

- UFC 53 Forrest Griffin’s and Nate Quarry’s first major UFC event, UFC debut was on TV

- Thiago Alves first major UFC event, UFC debut was on TV

- UFC 57 Liddell vs. Couture 3

- Keith Jardine and Brandon Vera’s first major UFC event UFC 57, UFC debut was on TV

Events information from Wikepedia.com

Also confirmed on fighters websites.