<P> The Seattle Seahawks are a professional American football franchise based in Seattle, Washington . The Seahawks compete in the National Football League (NFL) as a member club of the league's National Football Conference (NFC) West division . They joined the NFL in 1976 as an expansion team . The Seahawks are coached by Pete Carroll . Since 2002, they have played their home games at CenturyLink Field (formerly Qwest Field), located south of downtown Seattle . They previously played home games in the Kingdome (1976--1999) and Husky Stadium (1994, 2000--2001). </P> <P> Seahawks fans have been referred to collectively as the "12th Man", "12th Fan", or "12s". The Seahawks' fans have twice set the Guinness World Record for the loudest crowd noise at a sporting event, first registering 136.6 decibels during a game against the San Francisco 49ers in September 2013, and later during a Monday Night Football game against the New Orleans Saints a few months later, with a then record - setting 137.6 dB . The Seahawks are the only NFL franchise based in the Pacific Northwest region of North America, and thus attract support from a wide geographical area, including some parts of Oregon, Montana, Idaho, and Alaska, as well as Canadian fans in British Columbia, Alberta and Saskatchewan . </P> <P> Steve Largent, Cortez Kennedy, Walter Jones, and Kenny Easley have been voted into the Pro Football Hall of Fame primarily or wholly for their accomplishments as Seahawks . In addition to them, Dave Brown, Jacob Green, Dave Krieg, Curt Warner, and Jim Zorn have been inducted into the Seahawks Ring of Honor along with Pete Gross (radio announcer) and Chuck Knox (head coach). The Seahawks have won 10 division titles and three conference championships . They are the only team to have played in both the AFC and NFC Championship Games . They have appeared in three Super Bowls: losing 21--10 to the Pittsburgh Steelers in Super Bowl XL, defeating the Denver Broncos 43--8 for their first championship in Super Bowl XLVIII, and losing 28--24 to the New England Patriots in Super Bowl XLIX . </P> <P> As per one of the agreed parts of the 1970 AFL--NFL merger, the NFL began planning to expand from 26 to 28 teams . In June 1972, Seattle Professional Football Inc., a group of Seattle business and community leaders, announced its intention to acquire an NFL franchise for the city of Seattle . In June 1974, the NFL gave the city an expansion franchise . That December, NFL Commissioner Pete Rozelle announced the official signing of the franchise agreement by Lloyd W. Nordstrom, representing the Nordstrom family as majority partners for the consortium . </P>

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