The 'V and W Bug'

This may be straining the definition of 'classical music' very slightly, but we are now looking for the name of the American composer whose song about a train achieved the first Gold Disc in the weeks shortly after the USA actively entered World War Two: as such, Chattanooga Choo-Choo is an indisputable classic in its field and in the public ear at large.
This composer was no 'one-hit wonder': his score for 42nd Street alone includes plentiful other hummable items, and over 40 years he appears to have written some 800 songs. Who was he?

We are back among the true classics for our final tail-of-the-alphabet composer, who might fairly be defined as 'following Schubert and Schumann' as a composer ~ or setter ~ of Lieder (German art-songs), though a generation or so later he was taking the genre into fresh areas, particularly in regard to his harmonic innovations. It is, further, somehow appropriate that a successor to Schubert (who set many early Romantic poems about nature and folklore) should himself have a surname evocative of Grimm's fairy tales, and of the ambivalent relationship of people with the forested landscapes of central Europe.
Who was he?

Knighted for his services to music, principally the choral and orchestral repertoire, including film scores and iconic marches for national occasions, he shared his initials with the standard musical abbreviation for 'woodwind/s'. Who was he?

In English their names would, respectively, be Joe Green and Dick Carter; but in their original languages, these two were the colossi of opera in southern and northern Europe during the 19th century.
Who were they?

This is another British composer whose music you may (indeed, even should) know yet whose name you may not. He was born in Kent in 1903, studied with VW (as above) at the Royal College of Music, and after a stint as assistant organist at Rochester Cathedral ~ where he had been a chorister ~ spent the rest of his life based in Bournemouth, as a parish organist, and also as Borough Organist, playing the 4-manual Compton concert organ in the Pavilion Theatre. A lifelong sufferer from hypertension and TB, he survived the Second World War, only to die, blinded and of these principal medical causes, a few weeks shy of his 43rd birthday. His collections of organ miniatures (the 'Songs without words' of the British organ loft) are beautifully crafted, accessible and as such widely played and loved; many fine orchestral pieces have recently come to light and been recorded (see Naxos CD notes here; retrieved 27th of June 2014).
But who was this modest, amiable and capable musician?

This composer probably wouldn't leap into anyone's 'top ten', even within our current alphabetic limits, but if we reveal that he was Mozart's father-in-law (after Mozart had failed to woo one of Constanze's other three musical sisters), his calibre may begin to emerge. This principal composer had his first work published in Leipzig at the ripe age of 12 and went on to write three operas, besides much else ~ including numerous concerti for brass and woodwind instruments ~ and his influence on the Romantic generation of composers was considerable, with Berlioz referring to him repeatedly in his monumental treatise on orchestration.
Who was this composer?

This picaresque composer's assumed surname begins with a W but he was born Philip Heseltine, and possibly best remembered for his Capriol Suite, as well as a haunting setting of the carol Bethlehem Down. His creative muse appears to have run alongside a streak of mental or moral weakness, for while mixing with many great figures in the world of the arts he was prone to various forms of bingeing, and appears to have been responsible for his own death by gas poisoning shortly before Christmas 1930 in his own mid-thirties. It has since plausibly emerged that the distinctive and sometimes waspish art critic Brian Sewell (born two months after this event) was his love-child.
Anyway, by what name is this Heseltine better known to the music-loving public?

One very famous and relatively recent British composer comes doubly into this Quiz category since two of his names each fit within it: Ralph Vaughan Williams (often known with affectionate brevity as 'RVW'). His output included a cycle of nine symphonies, several successful film scores, and (despite him never having an active religious faith) the musical editing of not one, but two widely-used hymnbooks. The tune now almost universally sung to the Whit Sunday hymn Come down, o Love divine is named by VW for the Gloucestershire village in whose vicarage he was born: where was/is this?

One of the earliest classics of 'programme music' (i.e. descriptive) is the cycle of concerti The Four Seasons. Which of these composers was responsible for it?

Another Parisian organist, he composed several 'Symphonies' for the instrument, including his 5th (in 1879) whose glittering final movement was taken up, after about 80 years, by various European royalty as 'the' wedding recessional ~ initially, for Princess Margaret in 1960. The piece is known simply by the composer's surname and its own generic title ... as ... ?