Nathan Frederick Cayless is an Australian former professional rugby league footballer who played in the 1990s, 2000s and 2010s, and has coached in the 2010s. He played at representative level for New Zealand (captain), and at club level in the National Rugby League (NRL) for the Parramatta Eels, for whom he was a long-time captain, as a prop. He captained the New Zealand national team to a Rugby League World Cup victory over Australia in the 2008 Rugby League World Cup, and coached at club level in the Intrust Super Premiership for the Wentworthville Magpies from 2016 to 2018.

The New Zealand national rugby league team has represented New Zealand in rugby league since 1907. Administered by the New Zealand Rugby League, they are commonly known as the Kiwis, after the native bird of that name. The team's colours are black and white, with the dominant colour being black, and the players perform a haka before every match they play as a challenge to their opponents. The New Zealand Kiwis are currently second in the IRL World Rankings. Since the 1980s, most New Zealand representatives have been based overseas, in the professional National Rugby League and Super League competitions. Before that, players were selected entirely from clubs in domestic New Zealand leagues.