Short answers, pulled from the story.
Mahler's Symphony No. 2 is called the Resurrection Symphony because its finale sets a poem about rising from the dead. After hearing a setting of Friedrich Gottlieb Klopstock's resurrection poem at Hans von Bülow's funeral, Mahler used its first two verses and added his own verses about redemption and resurrection. It was his first major work to establish his lifelong view of the beauty of afterlife and resurrection.
Gustav Mahler wrote Symphony No. 2 between 1888 and 1894, and it was first performed in 1895. The first movement began life in 1888 as a single-movement symphonic poem called Totenfeier, and he composed the second and third movements in 1893.
Mahler's Symphony No. 2 has a duration of 80 to 90 minutes and is in five movements. It is conventionally labelled as being in the key of C minor, with its finale, the longest movement, typically lasting over half an hour.
The finale of Mahler's Symphony No. 2 uses the first eight lines of Friedrich Gottlieb Klopstock's poem Die Auferstehung, beginning Aufersteh'n. Mahler omitted the poem's final four lines and wrote the remaining verses himself, starting at O glaube. The fourth movement, Urlicht, is a song drawn from Des Knaben Wunderhorn.
The manuscript of Mahler's Symphony No. 2 sold at Sotheby's of London in 2016 for £4.5 million, the highest price ever attained for an auctioned musical manuscript. It is the only known handwritten and autographed manuscript of the work and is now housed at the Cleveland Museum of Art.
The first three movements of Mahler's Symphony No. 2 were premiered on the 4th of March 1895 in Berlin, with the composer conducting the Berlin Philharmonic. The complete symphony was first performed in Berlin on the 13th of December 1895, also conducted by Mahler.