Question: What conflict did the spouse of Maria Ley-Piscator fight in?

full_context: Document 1: Miami: This was also a period of alternatives to nightclubs, the warehouse party, acid house, rave and outdoor festival scenes of the late 1980s and early 1990s were havens for the latest trends in electronic dance music, especially house and its ever-more hypnotic, synthetic offspring techno and trance, in clubs like the infamous Warsaw Ballroom better known as Warsaw and The Mix where DJs like david padilla (who was the resident DJ for both) and radio. The new sound fed back into mainstream clubs across the country. The scene in SoBe, along with a bustling secondhand market for electronic instruments and turntables, had a strong democratizing effect, offering amateur, "bedroom" DJs the opportunity to become proficient and popular as both music players and producers, regardless of the whims of the professional music and club industries. Some of these notable DJs are John Benetiz (better known as JellyBean Benetiz), Danny Tenaglia, and David Padilla.
Document 2: Neues Schauspielhaus: While the auditorium was destroyed in World War II, the facade as well as the cinema survived and in 1951 was renamed the Metropol. Since 1977 it has been used as a discothèque and became a famous music club during the 1980s heyday of West Berlin, frequented by bands like Depeche Mode, Morrissey, The Cross, The Human League and Front 242. For a short time in 2000 it was the location of the KitKatClub and in 2005 the architect Hans Kollhoff remodeled the interior as the "Goya" night club.
Document 3: Warsaw: Warsaw's mixture of architectural styles reflects the turbulent history of the city and country. During the Second World War, Warsaw was razed to the ground by bombing raids and planned destruction. After liberation, rebuilding began as in other cities of the communist-ruled PRL. Most of the historical buildings were thoroughly reconstructed. However, some of the buildings from the 19th century that had been preserved in reasonably reconstructible form were nonetheless eradicated in the 1950s and 1960s (e.g. Leopold Kronenberg Palace). Mass residential blocks were erected, with basic design typical of Eastern bloc countries.
Document 4: 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 5: Ministries of Nineteen Eighty-Four: Orwell named Room 101 after a conference room at Broadcasting House where he used to sit through tedious meetings. When the original room 101 at the BBC was due to be demolished, a plaster cast of it was made by artist Rachel Whiteread and displayed in the cast courts of the Victoria and Albert Museum from November 2003 until June 2004.
Document 6: Frieda Lawrence: Frieda Lawrence (August 11, 1879 – August 11, 1956) was a German literary figure mainly known for her marriage to the British novelist D. H. Lawrence. She was a distant relative of Manfred von Richthofen, the "Red Baron".
Document 7: María Corda: She began her acting career in the theatres of Budapest in the early days of World War I and soon after the break-up of Austria-Hungary she also began to work in the film industry. Her first role was in "Se ki, se be" in 1919, directed by the Hungarian director, Korda Sandor, who would come to be known as Alexander Korda. She married Sandor, who was then the leading director in Hungary's fledgling film industry, in 1919. He featured her in three films that year "White Rose" ("Fehér rózsa"), "Ave Caesar!" and "Number 111" ("A 111-es") all of which he directed.
Document 8: Maria Ley-Piscator: Maria Ley-Piscator (born Friederike Flora Czada, 1 August 1898 – 14 October 1999) is best known as the wife of Erwin Piscator (1893–1966), Germany's famous left-wing theater director. Born on 1 August 1898 in Vienna, Austria-Hungary (now Austria), Maria Ley sought to create a theatrical career for herself as a dancer in Paris and Berlin. Later, she turned to choreography and helped in several stage productions with Max Reinhardt, including "A Midsummer Night's Dream".
Document 9: Studio 54: Studio 54 is a former nightclub and currently a Broadway theatre, located at 254 West 54th Street, between Eighth Avenue and Broadway in Midtown Manhattan, New York City. The building, originally built as the Gallo Opera House, opened in 1927, after which it changed names several times, eventually becoming CBS radio and television Studio 52.
Document 10: Richard Lert: Richard Lert (19 September 1885 - 25 April 1980) was an American conductor of Austrian birth. Born in Vienna, he was the younger brother of stage director Ernst Lert. After graduating with a music degree from the University of Vienna, he took a conducting post at the Opernhaus Düsseldorf in 1910. He left there in 1912 to take a similar position at the Opera in Darmstadt where he remained for four years. In 1916 he married novelist Vicki Baum and that same year joined the conducting staff of the Opern- und Schauspielhaus Frankfurt.
Document 11: Marion Freisler: Marion Freisler (10 February 1910 in Hamburg – 21 January 1997 in Munich), née Russegger was the wife of Roland Freisler, the infamous judge and chairman of the Nazi "Volksgerichtshof" (People's Court), who died in 1945 during an air raid in Berlin. She is sometimes mistakenly referred to as Anna Freisler.
Document 12: Viktor Léon: Victor Léon, also Viktor Léon (born Victor Hirschfeld; 4 January 1858, Szenic, Nyitra County, Kingdom of Hungary, Austrian Empire (today Senica, Slovakia) – 3 February 1940, Vienna) was a well-known Jewish Austrian-Hungarian librettist. He collaborated with Leo Stein to produce the libretto of Franz Lehár's romantic operetta "The Merry Widow" ("Die lustige Witwe").
Document 13: Lasipalatsi: An earlier building at the same location was the Turku barracks, which was destroyed in the Finnish Civil War in 1918. Lasipalatsi, designed by three young architects Viljo Revell, Heimo Riihimäki and Niilo Kokko, was built on the same site in 1936. Lasipalatsi, containing offices, restaurants and a film theatre, was originally designed as a temporary building, later to be torn down to allow a larger office building to be constructed in its place. The Varuboden grocery, Oy Siemens AB and the HOK ice cream bar were Lasipalatsi's most prominent businesses for decades. At the time of its opening, the film theatre Bio Rex was one of the biggest film theatres in the city, and many formal premieres of Finnish films were shown there.
Document 14: Gustav-Siegle-Haus: Gustav-Siegle-Haus is a music venue located in Stuttgart, Germany. The building was completed in 1912 by architect Theodor Fischer. The structure was rebuilt between 1953 and 1954 by architect Martin Elsaesser after it was destroyed by air raids during World War II. Past performers include Scorpions, Motörhead and AC/DC.
Document 15: Maria Caserini: From 1910 to 1927 she appeared in sixty five films, all produced in Italy, most of which were directed by her husband, and many of which were Shakespearean adaptations. She continued to perform in theater productions well after she left her film career. She was residing in Milan at the time of her death on 15 April 1969.
ground_truth: World War I
sub_queries: Maria Ley-Piscator >> spouse Answer: Erwin Piscator
Erwin Piscator >> conflict Answer: World War I