Yep, the Russians clearly saw it as a way up soften up Europe by creating division and chaos (job done).

I also presume there was cash coming in from American billionaires purely because just about every iffy astroturf campaign group seems to be partly or wholly funded by them in an attempt to drive the UK to the right and make it a low regulation zone where they can do what they like (although Liz Truss proved this approach was unworkable, at least in the short term).