Question: How many times did plague occur in the birthplace of the composer of Gloria in D Major?

Knowledge 1: Gloria (Vivaldi)
Antonio Vivaldi wrote at least three settings of the hymn Gloria in excelsis Deo, whose words date probably from the 4th Century and which is an integral part of the Ordinary of the Mass. Two survive: RV 588 and RV 589. A third, RV 590, is mentioned only in the Kreuzherren catalogue and presumed lost. The RV 589 Gloria is a familiar and popular piece among sacred works by Vivaldi. It was probably written at about the same time as the RV 588, possibly in 1715. [SEP] Knowledge 2: Orlando furioso (Vivaldi, 1714)
Orlando furioso RV 819 (, Teatro San Angelo, Venice 1714) is a three-act opera surviving in manuscript in Antonio Vivaldi's personal library, only partly related to his better known Orlando furioso (RV 728) of 1727. It is a recomposition of an "Orlando furioso" written by Giovanni Alberto Ristori which had been very successfully staged by Vivaldi and his father's "impresa" in 1713, and whose music survives in a few fragments retained in the score of RV 819. Therefore, Vivaldi's first cataloguer Peter Ryom did not assign the opera a RV number, but catalogued it as RV Anh. 84. The libretto was by Grazio Braccioli. [SEP] Knowledge 3: Black Death
In 1466, perhaps 40,000 people died of the plague in Paris. During the 16th and 17th centuries, the plague was present in Paris around 30 per cent of the time. The Black Death ravaged Europe for three years before it continued on into Russia, where the disease was present somewhere in the country 25 times between 1350 to 1490. Plague epidemics ravaged London in 1563, 1593, 1603, 1625, 1636, and 1665, reducing its population by 10 to 30% during those years. Over 10% of Amsterdam's population died in 1623–25, and again in 1635–36, 1655, and 1664. Plague occurred in Venice 22 times between 1361 and 1528. The plague of 1576–77 killed 50,000 in Venice, almost a third of the population. Late outbreaks in central Europe included the Italian Plague of 1629–1631, which is associated with troop movements during the Thirty Years' War, and the Great Plague of Vienna in 1679. Over 60% of Norway's population died in 1348–50. The last plague outbreak ravaged Oslo in 1654.
Knowledge 1: Gloria (Vivaldi)
Antonio Vivaldi wrote at least three settings of the hymn Gloria in excelsis Deo, whose words date probably from the 4th Century and which is an integral part of the Ordinary of the Mass. Two survive: RV 588 and RV 589. A third, RV 590, is mentioned only in the Kreuzherren catalogue and presumed lost. The RV 589 Gloria is a familiar and popular piece among sacred works by Vivaldi. It was probably written at about the same time as the RV 588, possibly in 1715. [SEP] Knowledge 2: Orlando furioso (Vivaldi, 1714)
Orlando furioso RV 819 (, Teatro San Angelo, Venice 1714) is a three-act opera surviving in manuscript in Antonio Vivaldi's personal library, only partly related to his better known Orlando furioso (RV 728) of 1727. It is a recomposition of an "Orlando furioso" written by Giovanni Alberto Ristori which had been very successfully staged by Vivaldi and his father's "impresa" in 1713, and whose music survives in a few fragments retained in the score of RV 819. Therefore, Vivaldi's first cataloguer Peter Ryom did not assign the opera a RV number, but catalogued it as RV Anh. 84. The libretto was by Grazio Braccioli. [SEP] Knowledge 3: Black Death
The Black Death ravaged much of the Islamic world. Plague was present in at least one location in the Islamic world virtually every year between 1500 and 1850. Plague repeatedly struck the cities of North Africa. Algiers lost 30 to 50 thousand inhabitants to it in 1620–21, and again in 1654–57, 1665, 1691, and 1740–42. Plague remained a major event in Ottoman society until the second quarter of the 19th century. Between 1701 and 1750, thirty-seven larger and smaller epidemics were recorded in Constantinople, and an additional thirty-one between 1751 and 1800. Baghdad has suffered severely from visitations of the plague, and sometimes two-thirds of its population has been wiped out.
Knowledge 1: Orlando furioso (Vivaldi, 1714)
Orlando furioso RV 819 (, Teatro San Angelo, Venice 1714) is a three-act opera surviving in manuscript in Antonio Vivaldi's personal library, only partly related to his better known Orlando furioso (RV 728) of 1727. It is a recomposition of an "Orlando furioso" written by Giovanni Alberto Ristori which had been very successfully staged by Vivaldi and his father's "impresa" in 1713, and whose music survives in a few fragments retained in the score of RV 819. Therefore, Vivaldi's first cataloguer Peter Ryom did not assign the opera a RV number, but catalogued it as RV Anh. 84. The libretto was by Grazio Braccioli. [SEP] Knowledge 2: Mandolin
Antonio Vivaldi composed a mandolin concerto (Concerto in C major Op.3 6) and two concertos for two mandolins and orchestra. Wolfgang Amadeus Mozart placed it in his 1787 work Don Giovanni and Beethoven created four variations of it. Antonio Maria Bononcini composed La conquista delle Spagne di Scipione Africano il giovane in 1707 and George Frideric Handel composed Alexander Balus in 1748. Others include Giovani Battista Gervasio (Sonata in D major for Mandolin and Basso Continuo), Giuseppe Giuliano (Sonata in D major for Mandolin and Basso Continuo), Emanuele Barbella (Sonata in D major for Mandolin and Basso Continuo), Domenico Scarlatti (Sonata n.54 (K.89) in D minor for Mandolin and Basso Continuo), and Addiego Guerra (Sonata in G major for Mandolin and Basso Continuo). [SEP] Knowledge 3: Black Death
In 1466, perhaps 40,000 people died of the plague in Paris. During the 16th and 17th centuries, the plague was present in Paris around 30 per cent of the time. The Black Death ravaged Europe for three years before it continued on into Russia, where the disease was present somewhere in the country 25 times between 1350 to 1490. Plague epidemics ravaged London in 1563, 1593, 1603, 1625, 1636, and 1665, reducing its population by 10 to 30% during those years. Over 10% of Amsterdam's population died in 1623–25, and again in 1635–36, 1655, and 1664. Plague occurred in Venice 22 times between 1361 and 1528. The plague of 1576–77 killed 50,000 in Venice, almost a third of the population. Late outbreaks in central Europe included the Italian Plague of 1629–1631, which is associated with troop movements during the Thirty Years' War, and the Great Plague of Vienna in 1679. Over 60% of Norway's population died in 1348–50. The last plague outbreak ravaged Oslo in 1654.

Answer: 22