The draw for the 15th edition of competition since being rebranded from the UEFA Cup was held in Monaco on Friday lunchtime.
Brighton's first-ever European campaign sees them pit their wits against former European Champions Ajax and Marseille and Greek champions AEK Athens.
Meanwhile, Jurgen Klopp's side will kick off their first Europa League campaign since losing the 2016 final to the competition's serial winners, Sevilla.
The Reds face Austrian outfit Lask, Union Saint-Gilloise of Belgium and French Cup holders Toulouse.
Last season's Europa Conference League winners West Ham face Greek side Olympiacos, Freiburg and debutants FK TSC Backa Topola of Serbia.
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Following their Champions League play-off defeat to PSV Eindhoven on Wednesday, Rangers will also contest this season's Europa League for the first time since a heartbreaking penalty shootout defeat to Eintracht Frankfurt in the 2022 final.
The Gers go head-to-head with La Liga side Real Betis, Sparta Prague and Aris Limassol.
The group stage kicks off on September 21 and ends on December 14 with the match calendar to be made available on Saturday.
This season's final will take place in Dublin on May 22.
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Europa League group stage draw in full
Group A: West Ham, Olympiacos, Freiburg, FK TSC Backa Topola
Group B: Ajax, Marseille, Brighton, AEK Athens
Group C: Rangers, Betis, Sparta Prague, Aris Limassol
Group D: Atalanta, Sporting Lisbon, Sturm Graz. Rakow
Group E: Liverpool, LASK, Union Saint-Gilloise, Toulouse
Group F: Villarreal, Rennes, Maccabi Haifa, Panathinaikos
Group G: Roma, Slavia Prague, Sheriff Tiraspol, Servette
Group H: Bayer Leverkusen, Qarabag, Molde, BK Hacken