There is more than one artist with this name.
1. A punk rock band from London, England
2. A rock band from Japan : RIGHT TAG is: ＣＨＥＬＳＥＡ
3. An indie pop band from France
4. A rock band from The United States Chelsea are an English punk rock band, formed in London in 1976. The original line-up was front-man Gene October, guitarist Billy Idol, Tony James (bass) and John Towe (drums, who had come from London SS along with James).

Read more about Chelsea on Last.fm.