[8] He made his first-team debut as a substitute in a League Cup tie against Sunderland on 25 October 2005, coming on for Arturo Lupoli in the 88th minute of a 3–0 win.

[9] Arsenal agreed a loan deal with Falkirk that saw Stokes play for the Scottish Premier League (SPL) side until the end of 2006.

[4][5] Celtic and Charlton Athletic had also been interested in the player, but Stokes revealed that he was greatly influenced by Sunderland manager and former Irish international, Roy Keane, in making his ultimate decision.

[26] Stokes started his time at Bramall Lane as a first team regular but was soon dropped to the bench and returned to Sunderland having made 12 appearances but failed to score a goal.

[27] In March 2009, Stokes joined Crystal Palace on loan, scoring from a solo effort after his first start against Preston North End.

After the match both Lennon and captain Scott Brown were critical of the referee, saying that decision cost Celtic the trophy and that it was a clear penalty.

[63] After Celtic's 2–1 defeat to Hearts in the Scottish Cup semi-final, Stokes was given a one-match ban for the competition following an "A5" incident at the end of the match.

[67] In December 2012, Stokes was disciplined by Celtic after he had attended a benefit event for Alan Ryan, a deceased member of the Real Irish Republican Army.

[75][76][77] Stokes was sent off against Motherwell on 18 January for a late tackle on Keith Lasley,[78] but on his return from suspension scored seven goals in nine games,[74] including a hat-trick against St Johnstone,[76] to double his tally for the season.

[80] Stokes scored another hat-trick on 27 April in a home league match against Inverness Caledonian Thistle, and also provided an assist for Griffiths in a 6–0 win.

[84][85] Stokes' form at this time was often unimpressive, drawing criticism from supporters,[86][87] and he was also disciplined by the club after he returned to Celtic late from a trip to his home city of Dublin.

"[88] A few days later, Stokes provided the assist for Jason Denayer's opening goal in a 4–0 win over Dundee United in a Scottish Cup quarter-final replay at Parkhead.

[90] By October he had made only two first team appearances, and in most games failed to even make the substitutes bench, with Deila again highlighting issues with his discipline.

[91] On failing to again even make the substitutes bench for a league match away at Inverness on 29 November, Stokes expressed his frustration in posts made on Twitter.

[93] The transfer window in January 2016 saw Stokes linked with loan moves to Hibernian and Inverness Caledonian Thistle, having not taken part in a first team game since 22 August 2015.

[97] At the end of the season, Stokes scored two goals in the 2016 Scottish Cup final and was named man of the match as Hibs won 3–2 against Rangers, their first win in the competition in 114 years.

[106] On 7 February 2018, days before the end of the Greek transfer window for unattached players, Stokes signed with Super League side Apollon Smyrni,[107] on an 18-month deal.

It did not take long for Stokes to get into trouble again; he went missing from training for a week in April 2018, with the club announcing in a statement that "we are looking if we can legally terminate his contract.

[118] In January, after a meeting in England with interim coach Mohammad Taghavi, Stokes decided to come back and play until the end of the season.

[120] Later, Tractor informed the Turkish side about the illegality of signing Stokes to a contract, without acquiring the consent of his current club and warned they could sue them and the player.

[128] Following Persepolis' match against Sharjah on 18 February, he obtained permission to stay in United Arab Emirates for one more day to visit his son.

[129] After remaining in UAE for longer that he was permitted, he announced that he did not intend to return to Iran due to the coronavirus pandemic there which led to him being fined by his club.

[136] Stokes earned his first full cap for the Republic of Ireland national football team in their 2–1 win away to San Marino on 7 February 2007, coming on as an 80th-minute substitute for Shane Long.

[141] In February 2012, Stokes said that he felt it was unlikely he would be picked for Ireland's squad for UEFA Euro 2012, despite good form for Celtic, as he thought Trapattoni was holding his 2011 withdrawal against him.

[143] He won his fifth cap in a 0–3 defeat away to Germany, a result which ended the Irish hopes of qualifying for the 2014 World Cup,[144] and also played four days later in a 3–1 home win over Kazakhstan.

[147] On 8 June 2013, Stokes attacked and head-butted car park attendant Anthony Bradley, in Buck Whaley's nightclub on Lower Leeson Street in Dublin.

Stokes subsequently agreed to pay Bradley €30,000 for breaking his nose and two of his teeth, in what was later described in court as a "nasty, cowardly attack".

He missed his sentencing in August 2022 due to contracting COVID-19 and did not attend the rescheduled hearing the following month, leading to an arrest warrant being issued by the sheriff.

[154] In January 2022, a prosecution for an alleged headbutting incident in Temple Bar, Dublin in March 2019 was struck out due to the failure of a witness to appear.

[155] On 6 January 2023, Stokes and another man were arrested in Crumlin, Dublin on suspicion of dangerous driving; the Gardaí allegedly found €4,500 worth of drugs in the vehicle.