Im not sure if whole story is clear here, before we judge.
Is it possible he needs to be outside own home maybe family member disabled?
Have you got 2 cars outside and he couldnt park his own?
I would next time you see him speak to him, apologise he may explain.
If a family member is significantly disabled, he can apply for a reserved disabled parking space to be painted, which only his family member or another blue badge holder is allowed to use.
If, as is extremely likely, he just likes having his own way and what suits him best, then it's just tough. There was somebody on a thread like this a while back who genuinely felt entitled to leave a 'please no parking' sign next to the space on the public road outside her house because she had young children! Such a rare situation for people to have children, eh - surely must have been the only one on the road and probably in the whole town!!
If you do have a genuine one-off reason for needing that spot - expecting an ambulance or funeral car/removal lorry coming first thing in the morning, then it's entirely possible to put up a polite sign (maybe on your bin, in the space or borrowing some cones) explaining it. Alternatively, you can even approach people in person and ask them in a friendly way if, just this once, they'd mind moving to let you have the space. Virtually nobody would decline to help out a pleasant neighbour. There's absolutely no reason or justification to be aggressive or intimidating about it.
If they do have two cars, then that means they've paid two lots of road tax, which entitles them to two spaces on the public road, on a first-come-first-served basis. he will be able to park his own car somewhere - just not in his preferred space. He may have a little walk to do so, but this is a scenario understood very well by anybody with half a brain who buys or rents a house without a drive or other private parking.
Exactly what do you propose they apologise to him for? For existing and wanting to park their car in a legal spot like anybody else and thus preventing him from living as the angry self-appointed king of the street? If they were to bizarrely apologise to him for some reason, that would give him the clear message that he can have whatever he wants as long as he's willing to intimidate, harass and be aggressive to the innocent people - who are just as entitled to it as he is - in order to take it from them.
And when I say 'people', I of course mean women, the elderly and other people he perceives as being weaker than he is. pound to a penny, if the door had been opened by a broad 25yo 6'6" rugby player, he would either have asked very nicely if his preferred space could be left for him or quite possibly bottled it completely and just said "Errrm, welcome to the street!"