I apologise if this isn't allowed here - I read the rules and they weren't clear - but we're in a pub in Kent and no one, not even the landlady, knows what is happening in this photo.
Can anyone identify the key figure(s), and fill in the context of when and what the parade is for?
I think it's Ramsgate, if that helps, and my reckoning is that it's a WWI victory parade. I'm happy to be shown wrong though!
Well it is in Ramsgate at least. I found the P.F. Weeks shop from a bit of googling - this local history site http://ramsgatehistory.com/index.html. However, I can't find any images of Harbour Street to match it up (pedestrianised now, so not on streetview). On a fairly interesting sidenote, P.F. Weeks had an MBE (search Percy Frank)
Looking at the image again, there's a Queen street sign above the shop one, so it must be on the corner here.
Best I can do for pictures is this view of the crossroads, with Harbour Street straight ahead and Queen Street to the right, meaning the parade would have come straight towards the camera.
Considering the last image (the space at the corner of the two streets), and also looking first at this view of the end of Harbour Street looking down the High Street in 1900 and then the same view from 2007 (from here), it's clear buildings in that area have changed quite a lot, presumably form bomb damage during WW2.
So in combination with canthinkof1ne's comment about the number plates, this must be some time between 1926 and 1940. I don't know if Edward would have done any royal visits after abdicating, so perhaps it can be narrowed down to 1926-1936. He might have done though, no idea.
I've found the answer. Found a clip from between 1920-1929 of a visit by Prince Edward to "Ramsgate, Broadstairs and Margate", from the beginning up to about 4.50. The whole video is interesting, shows Edward visiting Japan and the USA. This must be it, although there are no scenes similar to your picture, there are the three cars (can't make out number plates though), what looks like the same official (presumably mayor) and I think it unlikely he would visit the same town twice. He plants a tree, cuts a ribbon and shakes lot of official hands. So in your picture he was carrying out official royal duties, it wasn't for any particular occasion.
Speaking of mayors of Ramsgate, there are some fun photos of the wartime one, A.B.C. Kempe. Apparently he also built a network of tunnels beneath Ramsgate before the war had even started.
Questions about images are fine.
Through some google-fu, I found this--The Opening of Prince Edward Promenade in 1926. Could be the event in question. And the November date would fit within the registration plate dates.
Edit to add: Here's a photo from the opening. The guy on the right looks like the guy sitting next to Edward in the car--minus the (awesome) hat, but the voluptuous coat looks the same. I assume he's the mayor--F. C. Llewellyn?--I can't find a picture of him, though.
The two visible registration plates are from the year 1926, so it's sometime after then.
[YO - APR 1926 -> JUN 1926] (http://www.oldclassiccar.co.uk/registrations/yo.htm)
YP - JUN 1926 -> SEP 1926
I'm not sure, but I think the man in the car lifting his bowler hat may be Prince Bertie (later Edward VIII).