Question: Who founded the famous chain of music-themed restaurants which opened its first establishment in the city where Charles Albert Watts was born?

full_context: Document 1: Hard Rock Cafe: In 1990, The Rank Group, a London-based leisure company, acquired Mecca Leisure Group and continued expansion of the concept in its geographic territory. Rank went on to purchase Hard Rock America from Peter Morton as well as Hard Rock Canada from Nick Bitove. After the completion of these acquisitions, Rank gained worldwide control of the brand. In March 2007, the Seminole Tribe of Florida acquired Hard Rock Cafe International, Inc. and other related entities from Rank for US$965 million.In 2008, anonymous members of the wait staff criticized the business because of its practice of paying them less than half the official minimum wage in the UK, with the business allocating tips to staff to bring their salaries within the law. Most customers, it was argued, do not realize that they are subsidizing a low wage when they give the tip.
Document 2: Isaac Tigrett: On June 14, 1971 he and Peter Morton started the first Hard Rock Café (HRC) restaurant in London's fashionable Mayfair district. The restaurant combined rock music, memorabilia related to rock 'n' roll and American cuisine.
Document 3: Mexico City: The city is also a leading center of popular culture and music. There are a multitude of venues hosting Spanish and foreign-language performers. These include the 10,000-seat National Auditorium that regularly schedules the Spanish and English-language pop and rock artists, as well as many of the world's leading performing arts ensembles, the auditorium also broadcasts Grand Opera performances from New York's Metropolitan Opera on giant, high definition screens. In 2007 National Auditorium was selected world's best venue by multiple genre media.
Document 4: Hard Rock Cafe: The chain began to expand worldwide in 1982 with locations in (among others) Toronto, Los Angeles, San Francisco, Chicago, Paris, and Berlin. Hard Rock Cafe locations in the United States vary from smaller, more tourist driven markets (Biloxi, Pigeon Forge, Key West, etc.) to large metropolises (Houston, Philadelphia, New York City, Chicago, Boston, Washington, D.C., etc.). Hard Rock Cafe typically does not franchise cafe locations in the United States. All US cafes are corporate owned and operated, except for cafes in Tampa and Four Winds New Buffalo casino. However, in the transition of the Las Vegas Hard Rock Hotel property originally owned and then later sold to Rank by founder Peter Morton, Morton retained hotel naming rights west of the Mississippi. When Morton sold his Las Vegas Hard Rock Hotel to the Morgans Hotel Group, he also sold those naming rights, which then gave rise to two US franchised hotels (without cafes) in Albuquerque and Tulsa. The Albuquerque hotel no longer pays for the Hard Rock rights and reverted to its former name in June 2013. More hotels franchised from Morgan's are planned for Sioux City and Vancouver.
Document 5: Charles Albert Watts: Charles Albert Watts was the son of Charles Watts and his wife Kate Eunice Watts, and nephew of John Watts, all of whom were active in the rationalist and secularist movement in London, based around Charles Bradlaugh. John and Charles Watts both edited the "National Reformer", and founded a radical publishing house, Watts & Co., in London in 1864. Charles Watts co-founded the National Secular Society in 1866, and became a leading spokesman for the group after his brother's death, but broke with Bradlaugh in 1877 and, in 1883, emigrated to Toronto, Ontario, Canada, leaving his son Charles Albert to run his publishing house and continue his editorial work.
Document 6: Charles Wesley: Charles Wesley was the eighteenth child of Susanna Wesley and Samuel Wesley. He was born in Epworth, Lincolnshire, England, where his father was rector. He was educated at Westminster School and Christ Church, Oxford, where he was ordained. At Oxford, Charles formed a prayer group among his fellow students in 1727; his elder brother, John, joined in 1729, soon becoming its leader and moulding it in line with his own convictions. They focused on studying the Bible and living a holy life. Other students mocked them, saying they were the "Holy Club", "Sacramentarians", and "the Methodists", being methodical and exceptionally detailed in their Bible study, opinions and disciplined lifestyle. George Whitefield joined the group. After graduating with a master's degree in classical languages and literature, Charles followed his father and brother into Anglican orders in 1735.
Document 7: The Times: The third John Walter, the founder's grandson, succeeded his father in 1847. The paper continued as more or less independent, but from the 1850s The Times was beginning to suffer from the rise in competition from the penny press, notably The Daily Telegraph and The Morning Post.
Document 8: Karl Albrecht: Karl and Theo Albrecht were born and raised in a Catholic family in modest circumstances in Essen, Germany. Their father, Karl Sr, was employed as a miner and later as a baker's assistant. Their mother Anna, née Siepmann, had a small grocery store in the workers' quarter of Schonnebeck, a suburb of Essen. Theo completed an apprenticeship in his mother's store, while Karl worked in a delicatessen shop. Karl served in the Wehrmacht during World War II and was wounded on the Eastern Front. After the war, the brothers jointly took over their mother's business and founded Albrecht KG. They separated that company in 1961 into Aldi Nord, covering the part of Germany north of the Ruhr under Theo Albrecht, and Aldi Süd under Karl. The first Aldi (short for Albrecht Discount) was opened in 1962.
Document 9: London: London was instrumental in the development of punk music, with figures such as the Sex Pistols, The Clash, and Vivienne Westwood all based in the city. More recent artists to emerge from the London music scene include George Michael, Kate Bush, Seal, Siouxsie and the Banshees, Bush, the Spice Girls, Jamiroquai, Blur, The Prodigy, Gorillaz, Mumford & Sons, Coldplay, Amy Winehouse, Adele, Ed Sheeran and One Direction. London is also a centre for urban music. In particular the genres UK garage, drum and bass, dubstep and grime evolved in the city from the foreign genres of hip hop and reggae, alongside local drum and bass. Black music station BBC Radio 1Xtra was set up to support the rise of home-grown urban music both in London and in the rest of the UK.
Document 10: Isaac Tigrett: Isaac Burton Tigrett (born November 28, 1948, Jackson, Tennessee) is an American businessman, best known as the co-founder of Hard Rock Café and House of Blues.
Document 11: Hard Rock Hotel & Casino Atlantic City: Construction of what was originally known as the Taj Mahal commenced in 1983 by Resorts International, owner of the neighboring Resorts Casino Hotel, with an estimated budget of $250 million. Resorts head James Crosby said it might be named the United States Hotel, in reference to the city's first major hotel.
Document 12: London: London has numerous venues for rock and pop concerts, including the world's busiest arena the o2 arena and other large arenas such as Earls Court, Wembley Arena, as well as many mid-sized venues, such as Brixton Academy, the Hammersmith Apollo and the Shepherd's Bush Empire. Several music festivals, including the Wireless Festival, South West Four, Lovebox, and Hyde Park's British Summer Time are all held in London. The city is home to the first and original Hard Rock Cafe and the Abbey Road Studios where The Beatles recorded many of their hits. In the 1960s, 1970s and 1980s, musicians and groups like Elton John, Pink Floyd, David Bowie, Queen, The Kinks, The Rolling Stones, The Who, Eric Clapton, Led Zeppelin, The Small Faces, Iron Maiden, Fleetwood Mac, Elvis Costello, Cat Stevens, The Police, The Cure, Madness, The Jam, Dusty Springfield, Phil Collins, Rod Stewart and Sade, derived their sound from the streets and rhythms vibrating through London.
Document 13: Mexico City: Other popular sites for pop-artist performances include the 3,000-seat Teatro Metropolitan, the 15,000-seat Palacio de los Deportes, and the larger 50,000-seat Foro Sol Stadium, where popular international artists perform on a regular basis. The Cirque du Soleil has held several seasons at the Carpa Santa Fe, in the Santa Fe district in the western part of the city. There are numerous venues for smaller musical ensembles and solo performers. These include the Hard Rock Live, Bataclán, Foro Scotiabank, Lunario, Circo Volador and Voilá Acoustique. Recent additions include the 20,000-seat Arena Ciudad de México, the 3,000-seat Pepsi Center World Trade Center, and the 2,500-seat Auditorio Blackberry.
Document 14: Alan Tonks: Tonks is the son of the late Chris Alexander Tonks (1917-2006), who was a reeve (1957-1960) , deputy reeve, Board of Control member and alderman in what was first the Township and then the Borough of York (1969-1988) in Metropolitan Toronto. After graduating from York Memorial Collegiate Institute Tonk's father ran Tonks Hardware and Electric at 452 Rogers Road founded by his grandfather. Alan Tonks attended York University where he earned a Master's degree in political economy and the University of Toronto where he received a master's degree in education. He spent time working for a Canadian aid agency in Jamaica before becoming a junior high teacher for the Scarborough Board of Education for several years.
Document 15: Southampton: Southampton has two large live music venues, the Mayflower Theatre (formerly the Gaumont Theatre) and the Guildhall. The Guildhall has seen concerts from a wide range of popular artists including Pink Floyd, David Bowie, Delirious?, Manic Street Preachers, The Killers, The Kaiser Chiefs, Amy Winehouse, Lostprophets, The Midnight Beast, Modestep, and All Time Low. It also hosts classical concerts presented by the Bournemouth Symphony Orchestra, City of Southampton Orchestra, Southampton Concert Orchestra, Southampton Philharmonic Choir and Southampton Choral Society.
ground_truth: Peter Morton
sub_queries: What is Charles Albert Watts's birthplace? Answer: London
What famous chain of music-themed restaurants opened its first establishment in London ? Answer: Hard Rock Cafe
Hard Rock Cafe >> founded by Answer: Peter Morton