Question: In what year did the country where an MTV Unplugged performer is a citizen gain independence from Spain?

full_context: Document 1: Chihuahua (state): In 1562 Francisco de Ibarra headed a personal expedition in search of the mythical cities of Cibola and Quivira; he traveled through the present-day state of Chihuahua. Francisco de Ibarra is thought to have been the first European to see the ruins of Paquime. In 1564 Rodrigo de Río de Loza, a lieutenant under Francisco de Ibarra, stayed behind after the expedition and found gold at the foot of the mountains of the Sierra Madre Occidental; he founded the first Spanish city in the region, Santa Barbara in 1567 by bringing 400 European families to the settlement. A few years later in 1569 Franciscan missionaries led by Fray Agustín Rodríguez from the coast of Sinaloa and the state of Durango founded the first mission in the state in Valle de San Bartolomé (present-day Valle de Allende). Fray Agustín Rodríguez evangelized the native population until 1581. Between 1586 and 1588 a epidemic caused a temporary exodus of the small population in the territory of Nueva Vizcaya.
Document 2: Chihuahua (state): and Camargo. In 1631 Juan Rangel de Biezma discovered a rich vein of silver, and subsequently established San Jose del Parral near the site. Parral remained an important economic and cultural center for the next 300 years. On December 8, 1659 Fray García de San Francisco founded the mission of Nuestra Señora de Guadalupe de Mansos del Paso del Río del Norte and founded the town El Paso Del Norte (present day Ciudad Juárez) in 1667. The Spanish society that developed in the region replaced the sparse population of indigenous peoples. The absence of servants and workers forged the spirit of northern people as self-dependent, creative people that defended their European heritage. In 1680 settlers from Santa Fe, New Mexico sought refuge in El Paso Del Norte for twelve years after fleeing the attacks from Pueblo tribes, but returned to Santa Fe in 1692 after Diego de Vargas recaptured the city and vicinity. In 1709, Antonio de Deza y Ulloa founded the state capital Chihuahua City; shortly after, the city became the headquarters for the regional mining offices of the Spanish crown known as Real de Minas de San Francisco de Cuéllar in honor of the Viceroy of New Spain, Francisco Fernández de la Cueva Enríquez, Duke of Alburquerque and the Marquee of Cuéllar..
Document 3: Todo O Nada: After a five-year absence Benny Ibarra returned with Todo O Nada. This album features collaborations with Erik Rubin, Alix, Dougie Bowne and musicians from Café Tacuba and Alex González from the Mexican Rock band Maná . The first single, "Uno", was top of the charts for eight weeks, became a gold record in two weeks and later went to Platinum. The second single was "Inspiraciòn", also included in the film soundtrack of same name.
Document 4: El presente: "El presente" (English: ""The Present"") is a song by Julieta Venegas and is the first single from her album MTV Unplugged Julieta Venegas. Released on April 15, 2008. It is categorized as "A Worldwide Hit". The next song was placed in the top of Mexican radio, and Latin America and spent 11 weeks in the first place. The song was nominated for the Latin Grammy Award for Record of the Year and Song of the Year in 2008.
Document 5: Los Momentos: Los Momentos ("The Moments") is the sixth studio album by Mexican recording artist Julieta Venegas, was released 19 March 2013 by Sony Music Mexico. The first single from "Los Momentos" is "Tuve para dar". This album features collaborations with Cecilia Bastida, Natalia Lafourcade, Ana Tijoux and Rubén Albarrán (vocalist from Café Tacvba).
Document 6: Viva Duets: Viva Duets is a studio album by Tony Bennett, released in October 2012. The album is sung in English, Spanish and Portuguese; and features Latin American singers. Album's adaptations were written by Andres Castro, Edgar Barrera, Miguel Bosé, Ricardo Arjona, Kany Garcia, Thalia, Franco De Vita, Dani Martin, and Mario Molina Montez.
Document 7: History of San Antonio: The ``Villa de Bejar ''was founded by Spanish explorers on May 5th, 1718, by then Governor Martin Alarcon, at the headwaters of the San Pedro Creek. The mission San Antonio de Valero was established on the east bank of the creek and a presidio was 3 / 4 of a league downstream. Development of the Spanish colonial city followed. A trading post was also established near the presidio and the town developed as the capital of Tejas, a province of colonial Spain. It was the northernmost settlement associated with the Hispanic culture of the Valley of Mexico.
Document 8: Bendito Entre Las Mujeres: Bendito Entre Las Mujeres () is the first solo album by lead guitarist of Latin rock band Maná, Sergio Vallín. The album was released on September 22, 2009. On this album which he combines his signature guitar chops with the voices of some of the greatest female singers that includes Spaniards Ana Torroja (of the trio Mecano), Rosana, Natalia Jiménez (of La 5ª Estación), Paulina Rubio, Joy Huerta (of Jesse & Joy), Ely Guerra, Raquel del Rosario (of El Sueño de Morfeo), María José and Brazilian star Ivete Sangalo.
Document 9: Limón y Sal: Limón y Sal ("Lemon and Salt") is the title of the fourth studio album released by Mexican singer-songwriter Julieta Venegas. It was recorded in Buenos Aires, Argentina and first released in Mexico on May 30, 2006 and in the United States on June 6, 2006. To date the album has sold over 4.5 million copies worldwide.
Document 10: Tucson, Arizona: Jesuit missionary Eusebio Francisco Kino visited the Santa Cruz River valley in 1692, and founded the Mission San Xavier del Bac in 1700 about 7 mi (11 km) upstream from the site of the settlement of Tucson. A separate Convento settlement was founded downstream along the Santa Cruz River, near the base of what is now "A" mountain. Hugo O'Conor, the founding father of the city of Tucson, Arizona authorized the construction of a military fort in that location, Presidio San Agustín del Tucsón, on August 20, 1775 (near the present downtown Pima County Courthouse). During the Spanish period of the presidio, attacks such as the Second Battle of Tucson were repeatedly mounted by Apaches. Eventually the town came to be called "Tucson" and became a part of Sonora after Mexico gained independence from Spain in 1821.
Document 11: Aquí: Aquí ("Here") is the title of the debut studio album by Mexican singer-songwriter Julieta Venegas, released on March 24, 1997. It was well received by the public. The two singles released were "De Mis Pasos" and "Cómo Sé".
Document 12: Tucson, Arizona: Arizona, south of the Gila River was legally bought from Mexico in the Gadsden Purchase on June 8, 1854. Tucson became a part of the United States of America, although the American military did not formally take over control until March 1856. In 1857 Tucson became a stage station on the San Antonio-San Diego Mail Line and in 1858 became 3rd division headquarters of the Butterfield Overland Mail until the line shut down in March 1861. The Overland Mail Corporation attempted to continue running, however following the Bascom Affair, devastating Apache attacks on the stations and coaches ended operations in August 1861.[citation needed]
Document 13: Te Solte La Rienda: "Te Solte La Rienda" is the second radio single release and sixth track from Maná's second live album, "Maná MTV Unplugged" in 1999. "Te Solte La Rienda" is a song originally written by Mexican singer-songwriter in the Ranchera style José Alfredo Jiménez. On the week of September 25, 1999 the song debuted at number twenty nine on the U.S. Billboard Hot Latin Tracks. and just after one week later on October 2, 1999 it reach to its highest point at the number twenty one. It would stayed for a total of 4 weeks spot for one week. In 2002, Lupillo Rivera performed a cover of the song which peaked at #12 on the Hot Latin Songs and #2 on the Regional Mexican Songs chart.
Document 14: MTV Unplugged (Julieta Venegas album): MTV Unplugged is the first live album recorded by Mexican singer-songwriter Julieta Venegas. The album features a selection of her greatest hits, along with new tracks, including the singles "El Presente" and "Algún Día". A handful of guest artists was included: Gustavo Santaolalla, Natalia Lafourcade, Cuarteto Latinoamericano, La Mala Rodríguez. The album sold more than 2.5 million copies.
Document 15: ¡Mamma Mia!: ¡Mamma Mia! the tenth album by Mexican singer Verónica Castro, It was released in 1988. "Bienvenidos Aquí está" is the theme to Verónica Castro's late night show of the same name. The song "Bienvenidos Aquí está" was also sung in Italian by Gino Renni titled "Canzone esagerata (c’è chi c’ha)" as well as "Decir Adios" sung by Pupo - Fiordaliso titled "La Vita È Molto Di Più". She also won the "Antorcha de Plata" from Viña del Mar en 1989.
ground_truth: 1821
sub_queries: MTV Unplugged >> performer Answer: Julieta Venegas
Julieta Venegas >> country of citizenship Answer: Mexico
What year did Mexico gain independence from Spain? Answer: 1821