Short answers, pulled from the story.
Joseph Haydn was an Austrian composer of the Classical period who lived from 1732 to 1809. James Webster notes he is called the Father of the Symphony because he composed 107 symphonies, and he was pivotal in the evolution of chamber music forms like the string quartet and piano trio. He was also called Father of the String Quartet and Father of Sonata form.
Joseph Haydn spent much of his working life as music director for the wealthy Esterhazy family. He was hired in 1761 by Prince Paul Anton and served at palaces including Schloss Esterhazy in Eisenstadt and the grand new Esterhaza in rural Hungary. The isolation there led him to say he was "forced to become original."
Joseph Haydn, Mozart, and Beethoven are sometimes called the "First Viennese School." Haydn was a friend and mentor of Mozart, who returned the esteem in his "Haydn" quartets, and a teacher of Beethoven, who studied with him in Vienna. When Beethoven left Bonn in 1792, Count Waldstein wrote that he would receive the spirit of Mozart from the hands of Haydn.
Joseph Haydn travelled to London after the impresario Johann Peter Salomon offered him a lucrative deal to conduct new symphonies with a large orchestra. He left Vienna on the 15th of December 1790 and crossed the English Channel on New Year's Day of 1791, his first time seeing the sea. His two visits made him financially secure and produced works like the Surprise and London symphonies.
Joseph Haydn composed the oratorios The Creation in 1798 and The Seasons in 1801, working with his librettist Gottfried van Swieten. The Creation has a libretto based on the Book of Genesis, the Psalms, and John Milton's Paradise Lost. Each oratorio took him over a year to complete.
Joseph Haydn died peacefully in his own home in Vienna at 12:40 a.m. on the 31st of May 1809, aged 77, during the French bombardment of the city under Napoleon. His remains were moved to Eisenstadt in 1820, but his skull was stolen by phrenologists shortly after burial and only reunited with his other remains in 1954.