Original Puma trainingsshirt Barnsley F.C.

Barnsley Football Club is a professional football club based in Barnsley, South Yorkshire, England, which compete in EFL League One, the third tier of the English football league system. Nicknamed "the Tykes", they were founded in 1887 by Reverend Tiverton Preedy and moved into Oakwell stadium the following year. The club's colours were originally blue, but were changed to red and white in 1904. The club's main rivals are fellow Yorkshire clubs Sheffield Wednesday, Sheffield United, Leeds United, Huddersfield Town and Rotherham United.

Barnsley spent the 1890s in the Sheffield & District, Midland and Yorkshire leagues, before gaining admittance to the Football League Second Division in 1898. They twice reached the final of the FA Cup whilst still in the second tier, losing to Newcastle United in 1910 and winning the competition over West Bromwich Albion in 1912. The club suffered relegation in 1933, but secured promotion as Third Division North champions in 1934. They won the Third Division North title for a second time in 1939, having been relegated the previous season. Relegated again in 1953, they secured another Third Division North title in 1955. However, further relegations left them in the fourth tier of English football by 1966. Promotion from the Fourth Division was achieved in 1968, though they were relegated after just four seasons. The club secured two promotions in three years under the stewardship of Allan Clarke and Norman Hunter, and from 1981 would spend sixteen consecutive years in the second tier.

Premier League football was secured for the 1997–98 season with a second place finish in the First Division, though they were relegated after one season and dropped down to the third tier in 2002. Barnsley won the 2006 League One play-off final and remained in the Championship for eight seasons. Relegated in 2014, they won both the 2016 Football League Trophy final and the 2016 League One play-off final, though this time spent just two seasons in the Championship. In 2017, a majority stake in the club was sold to a consortium that included Chien Lee, Neerav Parekh and Billy Beane. Barnsley won promotion from League One with a second-place finish in 2019, before being relegated out of the Championship again in 2022. Barnsley have spent more seasons and played more games at the second level of English football than any other team.