Question: What was the nationality of the rock band that provided the namesake for a style of music leading to hardcore punk genre D-beat?

full_context: Document 1: List of Iron Maiden band members: Iron Maiden are a British heavy metal band formed in 1975 by bassist Steve Harris. After several lineup changes prior to their recording career, they settled on Harris, vocalist Paul Di'Anno, guitarist Dave Murray and drummer Doug Sampson. The band released an EP as a four-piece, before hiring guitarist Dennis Stratton in 1979. Doug Sampson was dismissed from the band as he was unable to cope with the touring schedule and, at the suggestion of Stratton, replaced by Clive Burr, with whom the band recorded their self-titled debut album in 1980. Later that year, Stratton was replaced by guitarist Adrian Smith, due to musical and personal differences brought about by choosing not to travel with the band when supporting Kiss on the European leg of their Unmasked Tour.
Document 2: Free (band): Free were an English rock band formed in London in 1968, best known for their 1970 signature song "All Right Now". They disbanded in 1973 and lead singer Paul Rodgers went on to become a frontman of the band Bad Company along with Simon Kirke on drums. Lead guitarist Paul Kossoff formed Back Street Crawler in 1975, but died from a pulmonary embolism at the age of 25 in 1976. Bassist Andy Fraser formed Sharks.
Document 3: Demons (band): Demons are a punk rock/garage punk band from Sweden. The band includes quotation marks in their name to differentiate themselves from other bands with a similar name. Their music has been described as "punk 'n' roll", but the band claims it should only be described as high-energy rock. Their musical style relies heavily on the energy derived from punk rock. Influences include 1960s garage rock bands such as The Sonics, The Standells and Shadows of Knight, The Velvet Underground, The Stooges and New York Dolls; and punk rock bands such as The Damned, The Heartbreakers and The Saints; and early hardcore punk bands such as Black Flag, Bad Brains and Dead Kennedys. "Demons" has often been compared to contemporary groups like New Bomb Turks, The Hellacopters and Electric Frankenstein.
Document 4: Kent Stax: Kent Stax is the original and current drummer of the DC hardcore punk band Scream, considered, with perhaps the exception of Minor Threat (both of these bands recorded on the now famous underground Dischord Records label), one of the most influential and successful hardcore punk band to emerge from the music movement which thrived during the 1980s. Along with brothers Franz and Peter Stahl and bassist Skeeter Thompson, Stax helped create the lightning-fast tempo that was a trademark of the punk rock genre. Considered one of the fastest and most energetic drummers in the field at that time, his talents lent themselves to keeping a thrashing powerful musical force under control, giving Scream its homegrown reputation as pioneers in the genre which transcended into some international notoriety. In the late eighties Stax left the band for personal reasons and David Grohl, a local drummer who was working with local band Dain Bramage replaced the longtime drummer. Stax played drums in a series of bands throughout the 1990s that drew influence from English punk and Oi music, most notably The Suspects (a band that had many muttering about a DC hardcore revival not seen since 1983) United 121 and Spitfires United. In the 2000s he played drums in the DC Oi-core band Alleged Bricks.
Document 5: List of Trapeze band members: Trapeze were an English rock band from Cannock, Staffordshire. Formed in March 1969, the band originally featured former The Montanas members John Jones (vocals, trumpet) and Terry Rowley (keyboards, guitar, flute), as well as former Finders Keepers members Mel Galley (guitar, vocals), Glenn Hughes (bass, piano, vocals) and Dave Holland (drums). After the band released their self-titled debut album in May 1970, Jones and Rowley left to return to The Montanas. Hughes, Galley and Holland released "Medusa" later in the year and "You Are the Music... We're Just the Band" in 1972, before Hughes left to join Deep Purple in June 1973. Prior to his departure, Hughes was due to switch to the role of second guitarist, with Pete MacKie set to take his place on bass; however, this never came to fruition.
Document 6: Grindcore: Grindcore is an extreme genre of music that originated in the early to mid-1980s. It draws inspiration from some of the most abrasive-sounding genres, including hardcore punk, extreme metal, industrial and noise rock. Grindcore is characterized by a noise-filled sound that uses heavily distorted, down-tuned guitars, grinding overdriven bass, high speed tempo, blast beats, and vocals which consist of growls and high-pitched shrieks. Early groups like Napalm Death are credited with laying the groundwork for the style. It is most prevalent today in North America and Europe, with popular contributors such as Brutal Truth and Nasum. Lyrical themes range from a primary focus on social and political concerns, to gory subject matter and black humor.
Document 7: Canadian hardcore punk: Canadian hardcore punk originated in the early 1980s. It was harder, faster, and heavier than the Canadian punk rock that preceded it. Hardcore punk (usually referred to simply as hardcore) is a punk rock music genre and subculture that originated in the late 1970s. The origin of the term "hardcore punk" is uncertain. The Vancouver-based band D.O.A. may have helped to popularize the term with the title of their 1981 album, "Hardcore '81". Hardcore historian Steven Blush said that the term "hardcore" is also a reference to the sense of being "fed up" with the existing punk and new wave music. Blush also states that the term refers to "an extreme: the absolute most Punk." One definition of the genre is "a form of exceptionally harsh punk rock."
Document 8: The Who: The Who are an English rock band that formed in 1964. Their classic line-up consisted of lead singer Roger Daltrey, guitarist and singer Pete Townshend, bass guitarist John Entwistle, and drummer Keith Moon. They are considered one of the most influential rock bands of the 20th century, selling over 100 million records worldwide and holding a reputation for their live shows and studio work.
Document 9: Discharge (band): Discharge are a British rock band formed in 1977 by Terence "Tezz" Roberts and Royston "Rainy" Wainwright. While the band had substantial line-up changes over its history, the classic line-up from the early 1980s featured bassist Wainwright, drummer Gary Maloney, Anthony "Bones" Roberts playing guitar, and vocalist Kelvin "Cal" Morris.
Document 10: D-beat: D-beat (also known as "discore", "kängpunk" (Swedish for "boot-punk"), and "discrust") is a style of hardcore punk, developed in the early 1980s by imitators of Discharge, after whom the genre is named, as well as a drum beat characteristic of this subgenre. D-beat is known for its "grinding, distorted and brutally political" sound. Discharge may have themselves inherited the beat from Motörhead and the Buzzcocks. D-beat is closely associated with crust punk, which is a heavier, more complex variation. The style was particularly popular in Sweden, and developed there by groups such as Crude SS, Anti Cimex, Mob 47 and Driller Killer. Other D-beat groups include Doom and the Varukers from the UK; Disclose from Japan; Crucifix and Final Conflict from the U.S.; Ratos de Porão, from Brazil; and MG15, from Spain. While the style initially developed in the early 1980s, a number of new groups working within the subgenre emerged in the mid-1990s. These include the Swedish groups Wolfbrigade, Totalitär, Avskum, Skitsystem and Disfear.
Document 11: Terry Disley: Terry Disley is a jazz keyboardist and composer who was born in London. While in London, Cannes and Los Angeles in the 1990s, he recorded with many artists including Bryan Ferry, Bon Jovi, Van Morrison, Sir Paul McCartney, George Harrison, Madness, Sir Mick Jagger, Terry Hall and Billy Bragg. For five years, he was also the musical director for Dave Stewart, contributing music for a whole range of albums and five major motion picture scores including "Showgirls", "Beautiful Girls" and "The Ref".
Document 12: List of Bad Company band members: The following list details musicians who have been and still are members of the American band Bad Company since its formation in 1973. The band's current lineup includes original members Simon Kirke (drums), Mick Ralphs (guitar) and Paul Rodgers (lead vocals) joined by latter members Howard Leese (guitar, formerly of Heart) and Todd Ronning (bass guitar). The band has gone through many lineup changes throughout its career. The only member to appear in every lineup is drummer Simon Kirke. He is the only member of the band to have performed at every Bad Company concert and to appear on every album. Mick Ralphs is currently still a part of the band but is being temporarily replaced by former Black Crowes guitarist Rich Robinson for the bands 2016 United States tour. While still officially a member of the band in 1990-1991, Ralphs also sat out most of their Holy Water tour. This time he was temporarily replaced by Geoff Whitehorn.
Document 13: Digital hardcore: Digital hardcore is a music genre that fuses hardcore punk and industrial rock with electronic music such as hardcore techno, breakcore and drum and bass. It typically features fast tempos and aggressive sound samples. The style was pioneered by Alec Empire of the German band Atari Teenage Riot during the early 1990s, and often has sociological or far-left lyrical themes.
Document 14: Hardcore punk: Hardcore punk (often abbreviated to hardcore) is a punk rock music genre and subculture that originated in the late 1970s. It is generally faster, harder, and more aggressive than other forms of punk rock. Its roots can be traced to earlier punk scenes in San Francisco and Southern California which arose as a reaction against the still predominant hippie cultural climate of the time. It was also inspired by New York punk rock and early proto-punk. New York punk had a harder-edged sound than its San Francisco counterpart, featuring anti-art expressions of masculine anger, energy and subversive humor. Hardcore punk generally disavows commercialism, the established music industry and "anything similar to the characteristics of mainstream rock" and often addresses social and political topics with "confrontational, politically-charged lyrics".
Document 15: The Sweet: The Sweet (also known as Sweet) is a British glam rock band that rose to worldwide fame in the 1970s. Their best known line-up consisted of lead vocalist Brian Connolly, bass player Steve Priest, guitarist Andy Scott, and drummer Mick Tucker. The group was originally called Sweetshop.
ground_truth: British