This tune has always sounded to me like one of those that originated as something else before being pressed into service by the rugger·bugger fraternity. Am I right?:—

Classical, perhaps [like say Dvorak's Humoresque or Ponchielli's Dance Of The Hours, both of which have done duty to carry Rugby·song type lyrics]?

Or music-hall?

Or even Sousa-or-other·march with march-rhythm slightly mucked about [cf Stars·n·Stripes·Forever or Col·Bogey].

Or did it indeed actually originate with its present well known "'Whatever' a Little Pig" shtick? Somehow my gut-instinct tells me otherwise.