William Slater is an Australian former professional rugby league footballer who played in the 2000s and 2010s. Slater is the current coach of the Queensland Maroons, whom he coached to victories in the 2022 and 2023 State of Origin series.

The Queensland rugby league team represents the Australian state of Queensland in rugby league football. Nicknamed the "Maroons" after the colour of their jersey, they play three times a year against arch-rivals New South Wales in the State of Origin series. The team is currently coached by Billy Slater and captained by Daly Cherry-Evans, and is administered by the Queensland Rugby League. They play all of their home matches at Brisbane's Lang Park.