Seattle Sounders FC is a professional soccer club based in Seattle, Washington. The team was founded in 2007 and began play in Major League Soccer (MLS) in 2009. The team has had a successful history in the league, winning the MLS Cup in 2016, 2017, and 2019, the Supporters’ Shield in 2014, and the U.S. Open Cup in 2009, 2010, 2011, 2014, 2015, and 2019.