[1] Notable players include: Paul Harragon, Robbie O'Davis, Danny Buderus and rugby league Immortal Andrew Johns.

The Newcastle Knights entered the New South Wales Rugby League (NSWRL) competition in 1988 with Allan McMahon as coach.

The Knights made the semi-finals again in 1995 when the competition became the Australian Rugby League (ARL), and won the reserve grade premiership the same year.

The Knights won the 1997 Australian Rugby League premiership, defeating the Manly-Warringah Sea Eagles 22–16 in the Grand Final.

This win was a huge morale boost to the district following the closure of the area's biggest employer, the BHP Newcastle Steelworks, being announced earlier the same year.

The three were suspended, despite O'Davis' claims the club was not notified his drug was banned until after his positive test, and MacDougall's medical reason for taking the steroids (his usage continued after he completed his suspension, now approved by the NRL).

The Knights came third in 2000, followed by a National Rugby League Premiership victory over the Parramatta Eels in 2001, with Andrew Johns winning the Clive Churchill Medal.

In 2006, the Knights finished the season in fourth position, a stunning reversal in form, but were eliminated from the finals after losing in the semi-final to the Brisbane Broncos, going down 50–6.

After making a promising start to the season with victories over contenders such as the Canterbury-Bankstown Bulldogs – the club and rugby league world was rocked by the shock retirement of Andrew Johns.

The club also struggled off-field, with Brian Smith's decision to release players such as Clint Newton, Kirk Reynoldson, and Josh Perry.

Before the final round of 2007, Tab Sportsbet's Glenn Munsie was reported in the Daily Telegraph saying that the Newcastle side were certainties for the 'wooden spoon' (coming last in the season) and "it was pointless taking money on the wooden spoon gong given Newcastle would be firmly planted at the bottom of the ladder by the end of the weekend".

[2] Despite these pressures, the Knights managed to avoid a second wooden spoon in three years – offloading the dreaded piece of 'silverware' to the Penrith Panthers with a last round victory over the Wests Tigers.

Towards the end of the season coach Brian Smith announced he was leaving Newcastle to join the troubled Sydney Roosters in 2010.

On 16 December 2009 it was announced player Danny Wicks was caught-up in a drug issue involving amphetamines, cocaine and ecstasy.

In March 2010 Chris Houston was served with notice to attend court on charges of supplying ecstasy and cocaine.

Captain Kurt Gidley succumbed to a shoulder injury early in the season which resulted in him missing the remainder of the year.

During the 2016 season, the club debuted 11 players in the NRL, while losing co-captain Tariq Sims midway through to year to go to St. George Illawarra.

[7] In December 2017, the Newcastle Knights expressed their interest in applying for a licence to participate in the inaugural NRL Women's season.

[9] The following season marked a resurgence for the club, with the arrivals of high-profile halfback Mitchell Pearce, sought after rookie fullback Kalyn Ponga, as well as Queensland Origin representative Aidan Guerra and several other players.

[15] Newcastle would end up finishing the 2023 NRL season in 5th place after winning nine straight matches, coming from 14th on the table after round 17.

On 11 June 2021, the Newcastle Knights were granted a licence to compete in the 2021 National Rugby League Women's (NRLW) competition.

[51] On the same day, the Knights announced a further six Newcastle and Hunter based signings in Bobbi Law from the Sydney Roosters, Jayme Fressard from the Brisbane Broncos and Georgia Page from the St. George Illawarra Dragons, as well as Phoebe Desmond, Chantelle Graham and Kyra Simon from local teams.

Six development players were also announced in Bree Chester, Sophie Clancy, Matilda Jones, Kayla Romaniuk, Jesse Southwell and Tylah Vallance.

[52] On 1 December 2021, the Knights signed nine Kiwi Ferns representatives in Ngatokotoru Arakua, Maitua Feterika, Annetta Nu'uausala, Charntay Poko, Krystal Rota, Charlotte Scanlan, Autumn-Rain Stephens-Daly, Katelyn Vaha'akolo and Kararaina Wira-Kohu,[53] Two days later, the club signed Romy Teitzel from the Brisbane Broncos, AFLW player Paige Parker, rugby sevens player Emma Sykes and North Queensland Gold Stars players Rangimarie Edwards-Bruce, Katie Green, Emma Manzelmann and Tahlulah Tillett.

[54] In January 2022, the Knights signed Kirra Dibb from the New Zealand Warriors after Emma Sykes withdrew from the squad.

[59] On 18 May 2022, the Knights announced the signing of Australian Jillaroos players Millie Boyle and Tamika Upton for their second season in the competition.