My family at the time were dockers and have talked about this and their involvement.There were without any doubt skirmishes that led the police to re-direct the black shirts to Hyde Park,if the march was unmolested why would the police suddenly at a whim re-direct? I have seen photos of Cable Street that show skirmishes taking place.In May 1940 Mosley was imprisoned and after the war moved abroad in disgrace as fascism failed.Jack Spot's involvement has been questioned but Alfie Solomons' boys were there. It was a cross community effort with Irish dockers, communist and socialist groups joining with local residents, many of whom were Jewish at the time.
The fighting was mainly between those groups and the police since Mosley was directed away from the area and ended up in Hyde Park.