Question: What is the nationality of the UFC Heavyweight Champion who attended the Art of War 12 Fighting Championship ? 

Context paragraphs:
UFC 102: UFC 102: Couture vs. Nogueira was a mixed martial arts pay-per-view event held by the Ultimate Fighting Championship (UFC) on August 29, 2009 at the Rose Garden in Portland, Oregon.  It featured former five-time UFC champion and UFC Hall of Famer Randy Couture, facing off against former PRIDE FC Heavyweight Champion and former Interim UFC Heavyweight Champion, Antônio Rodrigo Nogueira.

Randy Couture: Randall "Randy" Duane Couture ( ; born June 22, 1963) is an American actor, retired United States Army Sergeant, retired mixed martial artist and former collegiate and Greco-Roman wrestler.  During his tenures in the Ultimate Fighting Championship (UFC), Couture became a three-time UFC Heavyweight Champion, two-time UFC Light Heavyweight Champion, an interim UFC Light Heavyweight Champion and the UFC 13 Heavyweight Tournament Winner.  Couture is the first of only three fighters to hold two UFC championship titles in two different divisions (along with B.J. Penn and Conor McGregor).

Antônio Rodrigo Nogueira: Antônio Rodrigo Nogueira (] , born June 2, 1976), better known as Minotauro, is a semi-retired Brazilian mixed martial artist known for his technical mastery of Brazilian jiu-jitsu.  He won most of his fights via submissions.  He competed in the heavyweight division of the Ultimate Fighting Championship (UFC), where he is a former Interim UFC Heavyweight Champion.  He is the twin brother of UFC fighter Antônio Rogério Nogueira.  Nogueria rose to prominence in the Japanese promotion Pride Fighting Championships, where he was the first Pride Heavyweight Champion from November 2001 to March 2003, as well as a 2004 PRIDE FC Heavyweight Grand Prix Finalist.  He is one of only three men to have held championship titles in both Pride Fighting Championships and the Ultimate Fighting Championship (the others being Mauricio Rua and Mark Coleman).

Frank Mir: Francisco Santos "Frank" Mir, III (born May 24, 1979) is an American mixed martial artist, who competes for Bellator MMA in the Heavyweight division.  He formerly competed in the Ultimate Fighting Championship (UFC) for sixteen years.  A former UFC Heavyweight Champion, he currently holds the record for most fights, victories, and submissions in UFC Heavyweight history, and is tied for 4th most UFC victories overall.  Up until his release, Mir possessed the longest uninterrupted tenure of any fighter in UFC history.  He is the first man to knock out and submit Antônio Rodrigo Nogueira.

Dan Henderson: Daniel Jeffery Henderson (born August 24, 1970) is an American former mixed martial artist and Olympic wrestler, who last competed as a middleweight in the Ultimate Fighting Championship.  He was the last Strikeforce Light Heavyweight Champion and was the last Welterweight (80 kg ) and Middleweight (95 kg ) champion of Pride Fighting Championships.  Additionally, Henderson was the Brazil Open '97 Tournament Champion, the UFC 17 Middleweight Tournament Champion, the Rings: King of Kings 1999 Tournament Champion and the Pride Weltwerweight Grand Prix Tournament Champion.  During his career, Henderson also challenged for the UFC Middleweight Championship (2x), the UFC Light Heavyweight Championship and the Strikeforce Middleweight Championship.  He was the first mixed martial artist to concurrently hold two titles in two different weight classes in a major MMA promotion.  At the time of his retirement after UFC 204, he was the oldest fighter on the UFC roster.  Known to be one of the greatest mixed martial artists of all time having defeated a total of seventeen MMA world champions across four major MMA promotions (UFC, PRIDE FC, Strikeforce, and RINGS).

Tim Sylvia: Timothy Deane Sylvia (born March 5, 1976) is a retired American mixed martial arts (MMA) fighter, professional wrestler, and former two-time UFC Heavyweight Champion.  He has competed as a Super Heavyweight and Heavyweight.  While perhaps best known for competing in the UFC, Sylvia has also competed for Affliction, the International Fighting Championships (IFC), and ONE FC.

Team Tompkins: Team Tompkins is one of the camps participating in the International Fight League.  Coached by former UFC Heavyweight and Light Heavyweight Champion Randy Couture, Team Tompkins took the place of Team Xtreme Couture after a lawsuit from the UFC prevented former UFC Heavyweight champion Randy Couture from having any association with other MMA events while still technically under his UFC contract.

Vitor Belfort: Vitor Vieira Belfort (] ; born April 1, 1977) is a Brazilian mixed martial artist currently competing in the Middleweight division of the Ultimate Fighting Championship.  He is the former UFC Light Heavyweight Champion, UFC 12 Heavyweight Tournament Champion, and the Cage Rage World Light Heavyweight Champion.  As of June 16, 2017, he is the #11 contender in official UFC Middleweight rankings.

Renzo Gracie: Renzo Gracie ( ; ] ; born March 11, 1967) is a Brazilian mixed martial artist and Brazilian Jiu-Jitsu practitioner.  A member of the Gracie family of Brazil, Renzo is a 6th Degree Black in Brazilian Jiu-Jitsu under Carlos Gracie Jr..  He is the son of Robson Gracie, grandson of Carlos Gracie, nephew of Carlos Gracie, Jr. grandnephew of Helio Gracie, and the 1st cousin once removed of Royce Gracie.  In mixed martial arts, Renzo has competed in the Ultimate Fighting Championship, Pride Fighting Championships, K-1, RINGS, and International Fight League (head-coaching the New York Pitbulls).  He holds notable victories over five former UFC Champions: Frank Shamrock (UFC Light Heavyweight Champion), Carlos Newton (UFC Welterweight Champion), Pat Miletich (UFC Welterweight Champion), Maurice Smith (UFC Heavyweight Champion), and Oleg Taktarov (UFC 6 Tournament Winner)

Art of War Fighting Championship: The Art of War Fighting Championship (英雄榜/Art of War/AOW) is a Chinese professional mixed martial arts promotion based in Beijing, China.  The Chinese title "英雄榜" literally translated means "Gathering of Heroes."  Art of War FC has no relation to the defunct US MMA promotion Art of War Undisputed Arena Fighting Championship.  Art of War I was held at the Beijing Sports University on November 6, 2005.  The inaugural event made it the first professional mixed martial arts contest in the People's Republic of China.  To date, AOW has held 15 events in mainland China.  Its largest event was Art of War 12 - Invincible, held at the National Olympic Sports Center Auditorium in Beijing on May 23, 2009 to an audience of around 6,000 fans.  The event attracted many international guests, including former UFC Heavyweight Champion Tim Sylvia, renowned ring announcer Michael Buffer, and experienced referee "Big" John McCarthy.

Supporting paragraphs: Art of War Fighting Championship Tim Sylvia
Answer: American