HY is an Okinawan band composed of four men and one woman. The name HY came from the initials of Higashi Yakena, their hometown. They formed in high school, and debuted soon after their high school graduation in 2001.

HY released their first album, Departure, in limited quantities in Okinawa on September 22, 2001. On that same day they performed a street live at Okinawa Chatan Mihama Carnival Park, which at the time was a hot spot for Indies bands just starting out. They continued to perform there every weekend from the release of Departure until February 2002.

On March 23rd of 2002, HY performed a solo live on the Ginowan Beach Park outdoor stage, attracting an audience of around 3000, which was an impressive audience for an Indies band. They followed up their successful live with the nationwide release of Departure on April 10th 2002. They also performed on Music Station, one of the biggest music shows in Japan. HY also went to Paris and performed in The Fete de la Musique on June 21st.

From August 3rd to September 1st, HY went on their first nationwide tour, Summer Circuit Departure, which contained 10 concerts. In between they took part in many summer festivals, such as Summer Sonic 2002. They followed that up with a college campus tour, and then embarked on the Ocean '02 Tour, which started on November 28th. This was another nationwide tour lasting 6 concerts. Tickets for each concert were instantly sold out.

HY started 2003 out by releasing their second album, Street Story, on April 16th. This album debuted at #1 on the Oricon charts, making them the first Indies band in history to achieve that rank. It stayed #1 for four consecutive weeks, selling over a million copies shortly after the end of 2003. They were the second Indies band ever to have a million selling album.

On the same day as Street Story's release, HY embarked on their ASSE '03 TOUR, in which they performed in all 47 prefectures around Japan. The tour had a total of 54 concerts, and was a huge success.

As always, HY performed at various summer festivals in between tour performances, such as Setstock '03. 2003 was also full of split lives with foreign musicians, such as taking part in Summer Sonic '03 at Osaka and Tokyo with Radiohead, the strokes, and Stereophonics. On October 27th HY did a split live with Linkin Park at Nippon Budokan Hall. While certainly not the biggest concert hall in Japan, Budokan is quite possibly the most prestigious. HY ended 2003 with a performance at Music Station Super Live '03 in December, a four-hour live TV event with over 40 performing artists.

2004 started with the release of their third album, Trunk, on July 14th. Like Street Story it debuted at #1 on the Oricon charts, and while the sales weren't quite as high as Street Story, they were still very impressive, even compared to artists on big labels. On July 17th HY performed a street live in Mihama, attracting a crowd of around 5000. The following week they participated in THE ROCK ODESSY '04, and they participated in other summer festivals throughout the year.

On September 24th HY began their nationwide ITTA SOMUN '04 Tour, which lasted for 3 months. Each concert hall had an average capacity of 2000, performing to around 50,000 people by the tour's end. Each of the 26 concerts sold out in minutes. As in 2003 HY made another appearance in Music Station Super Live, which this time was held at the Saitama Super Arena and had over 50 artists present. The Saitama Super Arena seats approximately 30,000 people.

Unlike previous years, 2005 was a rather calm year for HY. On March 9th they released their first live DVD containing their final ITTA SOMUN performance in Okinawa. On July 31st they performed in Mihama, playing two unreleased songs that would be included on their next album. In August they released a special Red Style version of Departure, which was connected to their Premium Live Anshi Coke Nonjohnbar Rassai Tour, which contained seven concerts. They also participated in the summer festival, Rock in Japan.

HY started 2006 off by announcing their 4th album, Confidence, which released on April 12th and debuted at #1 on the charts yet again. They began their Watta Shinker tour on March 17th, however, which like the ASSE '03 TOUR took them to all 47 prefectures. By the end of the tour they had performed for close to 88,000 people.

In between concert tour performances they continued to participate in summer festivals, such as the Rising Sun Rock Festival and AP Bank Fest. In the AP Bank Fest they performed AM 11:00 with Kazutoshi Sakurai, who is the leader of one of the biggest bands in the Japanese music industry, Mr. Children.

In September 2006 HY announced their KUMAKARA AMAE Tour. This was a special tour, in which they would only perform at the Nippon Budokan Hall and Osaka-Jo Hall. These were both the largest concert halls they would have ever performed one-man-lives in, each seating around 14,000 people. Soon after announcing the tour, they announced that the performance at Budokan would be aired live on TV around Japan, and after that they renamed the Budokan performance "KUMAKARA AMAE Satellite Tour", as they decided to air it in locations ranging from Hokkaido to Okinawa via satellite, selling tour goods at each satellite broadcast location.

Tickets for both concerts sold out in a matter of minutes, and against their original plan, they opened up the seats behind the stage, which also sold out in minutes. The concert was a huge success, and in front of 14,000 people in Budokan and thousands around Japan, they announced their plans to perform once in Canada and 6 times around the USA in March.

After their successful performances at Budokan and Osaka-Jo, they finished the tour and the year 2006 off with a special street live at Mihama on Christmas Eve.

As planned, 2007 started off with the North American tour. They toured various bars around the USA with other bands as part of the Japan Nite '07, and after returning to Japan they began their "AMAKUMA A'CHA JAPAN" tour, in which they performed in many bars and nightclubs around Japan. On June 27th they released a documentary DVD concerning their Canadian/American tour and proceeded to perform in several summer festivals.

For 2008, HY kicked off with a special street live in Mihama in February at which they played some of their upcoming songs and announced their upcoming tour. The new album, HeartY, released on April 16th and the HY PACHINAIx32 BAMMICASUNDOH TOUR '08 began on May 16th and ended July 17th. Before this tour even began, HY also announced a following five-location large arena tour for September 25th through October 13th, PACHINAIx5 MAGGY HAKODE. Nearing the MAGGY HAKODE tour they added an additional performance in Yokohama and renamed the tour "PACHINAIx5 MAGGY HAKODE TOUR '08 & Nartyche".

During the MAGGY HAKODE tour HY announced their live plans for 2009 and 2010. On September 22nd, 2009 they would perform a special 10th anniversary street live in Mihama, and at an unspecified date they would embark on a Live House tour of 120 performances.

In addition to the 10th anniversary Street Live in 2009, HY also announced and recorded their 6th album, Whistle. The recording of Whistle took two months starting in June, and on October 30th they appeared on Music Station to perform Rail, for which they released a special limited CD containing it and two other samples from Whistle.

Details for the Live House tour were released on the same day as the 10th anniversary street live, and the number of performances jumped from 120 to 150, and later to 162.

The release of Whistle on January 27th started off 2010 and the band made appearances on several music shows to promote it. The Live House tour, MACHIKANTY SO-TANDOH TOUR, began on March 22nd at the Ginowan Beach Park outdoor stage in Okinawa and proceeded around the rest of Japan for nearly a full year. Along the way HY released several new songs without recording an official new album. Two were available on the ACHI SOUND live album, two were released as digital singles, and one was made available as a single song CD for sale throughout the MACHIKANTY SO-TANDOH TOUR.

New Year's Day 2012, HY announced their 7th upcoming album, PARADE, which released on March 7th. The band beefed up their promotion efforts with more TV appearances than usual, YouTube exposure, and a special Leap Day Live on February 29th. As an aside, HY also put out a limited rental CD which contained sample songs from each of their albums, plus one new song exclusive to the rental CD.

HY continued to promote PARADE from March 30th to May 13th with the TI-CHI TA-CHI MI-CHI PARADE TOUR, which included seven performances in large concert venues such as Nippon Budokan at five locations around Japan.

On November 28th HY released a second rental CD featuring a couple of songs from their 8th album, Route29, which was released on December 5th.