Background: Opeth is a Swedish heavy metal band from Stockholm, formed in 1989. The group has been through several personnel changes, but lead vocalist, guitarist and songwriter Mikael Akerfeldt has remained Opeth's primary driving force throughout the years. Opeth has consistently incorporated progressive, folk, blues, classical and jazz influences into its usually lengthy compositions, as well as strong influences from death metal, especially in their early works. Many songs include acoustic guitar passages and strong dynamic shifts, as well as both death growls and clean vocals.
Context: Opeth was formed as a death metal band in 1989 in Stockholm, Sweden, by lead vocalist David Isberg. Isberg asked former Eruption band member Mikael Akerfeldt (just 16 years old at the time) to join Opeth as a bassist. When Akerfeldt showed up to practice on the day after Isberg invited him, it became clear that Isberg had not told the band members, including the band's current bassist, that Akerfeldt would be joining. An ensuing argument led to all members but Isberg and Akerfeldt leaving to form a new project. The band name was derived from the word "Opet", taken from the Wilbur Smith novel The Sunbird. In this novel, Opet is the name of a fictional Phoenician city in South Africa translated as "City of the Moon".  Isberg and Akerfeldt recruited drummer Anders Nordin, bassist Nick Doring, and guitarist Andreas Dimeo. Unsatisfied with Opeth's slow progress, Doring and Dimeo left the band after their first performance, and were replaced by guitarist Kim Pettersson and bassist Johan De Farfalla. After the next show, De Farfalla left Opeth to spend time with his girlfriend in Germany, and was initially replaced by Mattias Ander, before Akerfeldt's friend Peter Lindgren took on the role of bassist. Rhythm guitarist Kim Pettersson left following the band's next performance, and Lindgren switched to guitar, with the role of bassist falling to Stefan Guteklint. The following year, David Isberg left the band citing "creative differences".  Following Isberg's departure, Akerfeldt took over vocal duties and he, Lindgren, and Nordin spent the next year writing and rehearsing new material. The group began to rely less on the blast beats and aggression typical of death metal, and incorporated acoustic guitars and guitar harmonies into their music; developing the core sound of Opeth. Bassist Guteklint was dismissed by the band after they signed their first record deal with Candlelight Records in 1994. Opeth initially employed former member De Farfalla as a session bassist for their demo recordings, and he went on to join on a full-time basis following the release of Opeth's debut album, "Orchid", in 1995.
Question: When did the band break up?. Whats the answer?