In their maiden season of 1999, Owner and Head Coach Scott lead the Jaguars to a 4-6 record. The 2000 season saw the Jaguars finish with the same 4-6 record.

During the 2002 season, the Jaguars went 4-4 for the season and French Field, located at Kent Meridian High School in Kent, became the official home field of the King County Jaguars.

In 2003 the King County Jaguars won the NWFL regular season title and won their first ever NWFL playoff game against the Multnomah County Buccaneers on September 6, 2003, by the score of 24 to 7. The Jaguars then advanced to the NWFL Championship game. The Jaguars came up short of the NWFL title loosing to the Eastside Hawks, (owned by the then Seattle Seahawk, Sam Adams), with a score of 27 to 17.

The 2003 season also brought the King County Jaguars their first ever North American Football League (NAFL) playoff game against the South Ogden Rhino-Raiders in Utah. The Jaguars traveled to Utah and lost by the score of 20-2.

In 2004 the Jaguars finished the NWFL regular season with an 8-2 record and an 8-4 overall record. The Jaguars again traveled to play the South Ogden Rhino-Raiders in a national playoff game and lost 34-18.

In 2005 the Jaguar organization brought on a new General Manager, Lorrie Jean Rarey. Ms. Rarey, a Certified Public Accountant with a firm in Auburn, Washington was a valuable addition to the business side of the organization. Rarey brought on a skilled (volunteer) staff to help with the organizations administrative duties and game day preparations. With the business administration, staffing and finances of the organization being handled by Rarey, Coach Scott was able to focus his full attention on the team. He then compiled a team of football players with outstanding ability, and a coaching staff with years of football experience. This nucleus of combined talent produced the greatest team in King County Jaguar history.

2005 saw the Jaguars win the NWFL Championship 21 to 6 over the West Sound Saints of Silverdale, Washington. As NWFL champions the 2005 King County Jaguar team entered into the NAFL national tournament. The Jaguars advanced all the way to the NAFL Championship game at Disney's Wide World of Sports complex in Orlando, Florida. There they competed against the three time NAFL Champion Central Pennsylvania Piranha team. The Piranha defeated the Jaguars by the score of 28 to 3.

The 2005 Jaguars advanced to the NAFL championship game by defeating two undefeated teams: the Dallas Diesel 27-24, and the Arkansas Rhinos 55-22. The King County Jaguars ended their 2005 season as the 2005 Minor League Football News #1 AAA Ranked Western Regional Summer/Fall Semi-Professional football team. The Jaguars had their best winning season ever with an overall record of 14-1.

In 2006 the King County Jaguars defended their 2005 NWFL title, again defeating the West Sound Saints in the NWFL Championship with a score of 14 to 7. In that same year the King County Jaguars became members of the Minor League Football Association (MLFA West). The Jaguars played for the MLFA West National Championship against the Bay Tickets Inc. 49ers at Golden Gate Park's historic Kezar Stadium in San Francisco, CA. In this championship game the Jaguars held the lead against the home town 49er team at 14 to 13 for most of the game, but with 7 seconds remaining in the game the 49ers kicked a 25 yard field goal to win the game 16-14.

For 2006, the Jaguars were also the champions of the first ever Kent Cornucopia Bowl. The Jaguars finished their 2006 season with an overall record of 11-1.

On April 1, 2007 the structure and ownership of the Jaguars changed. The team is now owned and operated by King County Jaguars Football, LLC, an ownership group that consisted of Jaguars long time owner, Jeff Scott, General Manager, Lorrie Jean Rarey and her husband Rob Rarey and Norm Larson and his wife Kim Larson, Norm is a prominent local businessman. Norm and his wife Kim have been long time supporters of the Jaguars through their company, Centre Pointe Consulting. The Larson’s are also the owners of the Big Red Barn, a historical building in downtown Kent.

In 2007 the King County Jaguars won their third consecutive Northwest Football League Championship, the Minor League Football Association West National Championship (by defeating the Blue Mountain Stars 29-0) and the NAFL Pacific Coast Division title. On October 27th, the Jaguars faced the defending NAFL National Champion, Dallas TX Diesel, in round four of the NAFL playoffs. The Jaguars scored late in the 4th quarter to take the lead on the Diesel 19-18 but on Dallas's next possession, the Diesel drove the ball down field getting close enough to kick a 31 yard field goal with 34 seconds remaining in the game. With less than a minute left, the Jaguars were unable to get within field goal range and lost the game 21-19. The Jaguars finished the 2007 season ranked #5 in the nation by the Minor League Football News poll and #1 of all 5 Northwest leagues, (a total of 38 teams) with a 14-1 season record.

After the Jaguars heartbreaking loss to the Dallas Diesel in the fourth round of the 2007 NAFL playoffs, owner and Head Coach Jeff Scott made the difficult decision to retire from coaching. He subsequently relinquished his remaining ownership in the organization and is now starting a new team in the Northwest Football League, the Puget Sound Titans.

At the end of the 2007 season, the Jaguar ownership group made the decision to leave the Northwest Football League, where they had played since their inception, and moved fully into the North American Football League.

November 12, 2007 King County Jaguar WR Anthony Montgomery was named the 2007 North American Football League National All-Star Player of the Game in Vegas Nevada. On December 8, 2007 Jaguars long time Coach, Jeff Scott, was inducted into the Minor-League Football Hall of Fame in Mesquite Nevada.

On January 4, 2008 the King County Jaguars announced the hiring of veteran player and coach, Mike Astley, as the Jaguars new Head Coach.

LB Dion Alexander, K/P Mike Astley, LB Robert Brown, WR Michael Bush, CB Jeremiah Captain, WR Carlos Clark, FB Malachi DeWalt, DT Fred Hardwell, DE Shawn Lovelace, S KR Milton Myers, QB James Phillips, RB Nathan Proctor, OT Chris Rarey, DE Terrance Stitt, OT Ryan Wood, WR Anthony Montgomery, QB Leo Dickerson, FB Nathan Proctor, OG Andrew Pina, DL Mitch Johnson, LB Willie Stewart, DL Washington Mose, DT Tutu Tamaalevea, CB Duane Bowen, FS, WR, QB Kenneth Jackson, FS Nathan Hale III, RB Vernon Word, TE Matt Cole, C Ronald Livingston, OG Keith Jones, OT Jon Hammersmark, OT Larry Fowler, KR Delano Edgecomb, FB Geoff Mollichi, RB Andre Edwards, WR Hakeem McAllister, OG Rashaad Fontenot, OT Khaleeq Abdul Al Aziz, K Andre Zahajko, DL Nick Caldwell, LB Keaka Frank, SS Denetric Williams, SS Lehman Jones, CB Anthony Gaynes, SS Jeff Hill, FS Dino Williams, WR Rico Brown, TE Landon Bishop, C Vic Tuli, OG Dave Melugin, OT Gregg Kinnunen, K Richard Black, DL Tony Bates, DL Jackie Triplett, DL D. Caldwell, LB Tommy Thompson, SS Denetric Williams, CB Cedric Mars, OG Marquise Richards, CB Ernie Populus, P Mike Reidy, KR Michael Bible, DL Toby Delgado, KR Michael Dwyer, DL Eric Green, S Brett Weiburg, CB Darrald Gainer, QB Derrick Smith, WR Derrick Smith, FS Chuck Jackson, KR RB Dwayne Buckley