The Yellow Scarves was founded by the middle schooler Masaomi Kida and his group of friends. The Yellow Scarves began as a way to find adventure and have fun. They would go around the city in a large group and spend their whole day fighting. The leader soon began a relationship with a girl he met in the city named Saki, and in turn met the information broker Izaya Orihara. The Yellow Scarves were in a constant battle with the Blue Square color gang. Whenever Kida was unaware of what he should do, he would ask Saki, who would then suggest he talk to Izaya. Frustrated with the constant casualties the gang has taken, Kida decided to rely on the information Izaya could give him. This resulted in a turn in power between the two groups. The Yellow Scarves were in complete control. The Blue Squares decided to take drastic measures and kidnap Saki, the leader's girlfriend and dealing severe injury to her legs, breaking them so that she no longer could walk. With the leader of the Yellow Scarves helpless, Kyohei Kadota, after hearing what the Blue Square had done, defected from the gang and rescued Saki with help from his own group. Soon after, the Blue Squares disbanded and Masaomi Kida resigned as a member of the Yellow Scarves.
Even with the defection of their leader Masaomi Kida, the Yellow Scarves continued to roam the streets of Ikebukuro. They maintained their notorious reputation by causing trouble and attacking people on the streets.
The Yellow Scarves soon found themselves helpless when rumors about "The Black Rider" and The Slasher incidents began. In fear of them losing control of the city, they attempted to re-recruit their former leader Masaomi Kida, but he refused to return. He later changed his mind after a Slasher incident resulted in his close friend Anri Sonohara being hospitalized. They came to the conclusion that The Slasher, The Black Rider, and The Dollars are working together. This made the Dollars a prime target for the Yellow Scarves. Their objective was to find as much information as they can on The Slasher and the Dollars, but not to cause any harm or trouble. The members, acting out of order, began beating up anyone they would believe was a Dollars member. The Dollars took their first casualty when a group of older Yellow Scarves members led by Horada sent Ryo Takiguchi to the hospital.
The Yellow Scarves' members initially consisted of young middle schoolers recruited by Masaomi Kida. After his departure the gang continued to grow and began to include older members.
Members of the Yellow Scarves are identified by their color yellow. They'd be seen with yellow bandannas or scarves around their neck, otherwise it'd be any other yellow attire such as hats, hoodies, jackets or shirts.
At the time of the series, the Yellow Scarves contains some Dollars members, many former Blue Squares, and some people stabbed by Saika.
- The name "Yellow Scarves" is a reference to the Yellow Turban Rebellion which opens The Romance of The Three Kingdoms. The Rebellion's slogan was “The Blue Sky has perished, the Yellow Sky will soon rise; in this year of Jia Zi, let there be prosperity in the world!” (蒼天已死，黃天當立。歲在甲子，天下大吉。). In the context of the original rebellion, the Blue Sky was a reference to the Han Dynasty, the Yellow Sky was the rebellion. The first four kanji of this slogan are seen spraypainted outside the Yellow Scarves' hideout in Episode 19 and are the title of the episode. The title the next episode is the second set of kanji, 黃天當立 or " the Yellow Sky will soon rise."