What is it specifically about the UK that meant that the revolutionaries among the working class predominantly opted for Marxism and specifically Leninism? Was it the presence of a parliament to which sufferage was being won? Was it, further more, the presence of a mass party of the trade union movement, Labour, which belonged to the Social Democratic tradition which made the hop, skip and jump to Leninism easier? Or were there other reasons?
On a similar subject even before I made the jump from Leninism to anarchism I always loved the following quote, it is so moving and evocative.
"Anarchism has thriven best in lands of the sun, where it is easy to dream of golden ages of ease and simplicity, yet where the clear light also heightens the shadows of existing misery. It is the men of the South who have flocked in their thousands to the black banners of anarchic revolt, the Italians and Andalusians and Ukrainians, the men of Lyons and Marseilles, of Naples and Barcelona." Anarchism by George Woodcock.
I don't think Anarchism did take hold in the US any more than it did in the UK. If your talking early last century and late the one before.
It took of in Spain because it chimed with the already existing way of life in the pueblos, small villages.