The best thing about state socialist May Days were the balloons. As a kid, I usually got a balloon and cotton candy at the fair after the official parade. The fair–with cheap food, beer and entertainment–was a kind of reward to the people for marching under banners with slogans like “Forward on the road of socialism!”
The participants of the parades (held in all cities) were organized by workplace: the factories, institutions, schools etc. were supposed to send a certain number of people equipped with banners and paraphernalia representing their workplace and line of work. The choreography and visual appearance of the May Day celebrations did not change much over the decades (the first four pictures are from the 1950s and the last three from the 1970s). By the 1980s they were pretty much empty rituals, which still had a vital function. What was expected from the population was not so much that they believe the slogans (and the ideology behind them) but that they participate–in person or in front of their television sets watching the day-long broadcast from Budapest.