In fact there's an older immigrant musical tradition than the Captain's original message implies, though it wasn't one which had a lasting impact in England.

I grew up in Nottingham, a town which saw a fair deal of immigration following the end of WW2. Many of the Polish and Ukrainian male emigrants, as well as those from Latvia, Lithuania and Estonia, had come over during the war and established new lives after its cessation, in many cases somehow managing to bring their families too.

When I was growing up in the 60s you could buy all the Polish and Baltic newspapers in Nottingham and there was an extremely active social scene. The best of these was The Polish Club, though it was hard pushed by the Ukrainian venue. As I recall, the music was pretty bland and largely dancehall influenced (in the swing band style). Indeed none of my school classmates from those communities had much of an idea about their own musical traditions.

Yet I also spent many an evening with the families of my friends and heard many a Russian or Polish song, or similar songs from the Ukraine or the Baltic, always sung by their parents or grandparents. Sadly, none seemed to pass down to the succeeding generations.