Composed by minGtion, Anne Judith Stokke Wik, Moa "Cazzi Opeia" Carlebecker, and Ellen Berg with Korean lyrics adapted by Jo Yoon-kyung, the dance-pop song was released as the titular EP's lead single on August 16, 2021, by SM Entertainment, along with its accompanying music video.

After a year and eight months, SM Entertainment confirmed through Newsen on June 9, 2021, that Red Velvet will be preparing a new album with the aim of making a comeback in August.

[6] "Queendom" was composed by minGtion, Anne Judith Stokke Wik, Moa "Cazzi Opeia" Carlebecker, and Ellen Berg, while the Korean lyrics were written by Jo Yoon-kyung.

[7] In a newspaper interview with The Post, Wik revealed that the writer's table for the song was four women, and called it "impressive", reasoning that the music industry is male-dominated.

[8] In an interview made by Vogue with Red Velvet, Wendy revealed that the group had put a lot of thought towards "expressing and showcasing" differently their "unique colors".

The group had come up with an idea of storytelling three different concepts which were, "homecoming", "journey", and "carnival", while stating that listening to their song would bring their feeling of "bright and positive energy".

[13] Tamar Herman of South China Morning Post recognized the "lusher synth styling" on which it balanced a "catchy, magical spell-like" chorus, "That's our queendom yeah/Ladida-do Ba-badida).

[17] Kim Sung-yeop of IZM noted the song for thoroughly focusing on the message and sensibility, giving an example of the lyrics, "Shall we start again", as it contains an autobiographical story of moving towards a new beginning of Red Velvet.

Moreover, Kim described the lyrics, "Ladida-do Ba-badida", as a track that does not "create synergy with the ambiguous concept song" and refuses to offset the plain impression of the overall melody.

JT Early of Beats Per Minute described the song as "vivacious and uplifting" with its "more laid-back and magical vibe", calling it as "the perfect return track".

[14] Lee Jin-joo of BNT News expressed that unlike the experimental concept that Red Velvet had shown for a while, the group have "embodied their own colors" with familiar and popular music.

[20] Verónica Bastardo of The Quietus called it a "light and fun electronic club song", further adding that it would be a great track for party vibes chants.

Yoon disclosed that Lee pointed out every details such as the direction in which Seulgi's side hair falls in the scene where she is riding her golf cart.

[62] The music video for "Queendom" is set in a "blindingly vibrant" Alice In Wonderland-esque world with a series of magical corridors taking Red Velvet across different realms.

[65] On August 12, 2021, Red Velvet appeared on the YouTube channel, Civilization Express - MMTG, for their comeback special along with MC Jaejae, where they performed "Queendom" for the first time.