One similarity that unions in almost every country had is that they were seen as being dangerous by different govts. As a result, unions (and socialist parties) were compelled to find ways to keep their activities as free as possible from state intervention.

In my studies (my PhD is about the working class in pre WW1 Romania) I found different ways used by unionists and social-democrats to still meet while the police tried to stopped them. One instance is quite funny. In 1907 CGSR congress(general council of Romanian unions) was held in Galați. Earlier that year, the country was shaken by a violent peasant uprising, the last peasant uprising in Europe and the liberal govt. of the time was weary about this congress and tried to stop it. The delegates were not allowed in the city and thus they ended up in a lake nearby where they got undressed and took a bath. The police ordered them to go out and leave, but they did not want to wet themselves in order to snatch the union leaders from the water. Seeing this, they started having their congress while in the lake.

What are some other interesting stories regarding unions in other countries?

Да здравствует первое мая, товарищи!

It's been a long week, and it's only Tuesday, but cut me some slack — last week was a long week too. The thing is, I actually have some pretty good working conditions, it's only that we're seemingly always a little understaffed, because we were building a new structure to store stuff on, and that required us to sacrifice a person to the wood shop each day for the past three weeks. (Metaphorically.) But now the structure is built, so things should be a lot cleaner, and we should be a lot better about staffing. All of that, as tangentially related to workers' rights as it is, is an excuse, though, for why I'm about to repost an older answer of mine about working conditions on the Moscow Metro in the 1930s. So enjoy.

The Contours of Policy, 1917–1939

First, it's worth mentioning by way of introduction that the Soviet job market was still largely a market. The economy of the former Russian Empire almost entirely collapsed in the very early 1920s, just as the Civil War in European Russia was winding down and into the early 1920s, and in the emergency of the war, people certainly were pressed into jobs they might not otherwise have enjoyed doing — the middle-aged historian and diarist Yuri Gotye, for example, was enlisted to clean streets and chop firewood. In the factories, meanwhile, many of which were home to pro-Bolshevik unions, there was a high degree of worker democracy.

However, as society recovered from the war and the Soviet Union was officially formed in the early 1920s, the Bolsheviks introduced a series of policies known as the New Economic Policy (NEP), which once again returned many factory leadership positions to appointment rather than election, and allowed free trade on grain, business, speculation, and money. For the rest of the Soviet Union's existence, there would be money to work for, and depending on the exact period we're talking about, high wages and cash prizes might be a very effective way to get people to perform dangerous and difficult jobs.

Part of the NEP, in fact, was the end of the wage equalization policies that the Bolsheviks had tried to put in place in the early days of Soviet power. It had proven difficult to make skilled workers want to do their jobs during the Civil War, so over the mid-1920s, wage equalization was replaced by differentiation, where workers were rewarded for producing above their quota. The late 1920s, a period of Leftist ascendancy retroactively labeled the "Cultural Revolution," marked a return to equalization, so Soviet authorities introduced other measures to make workers want to work, such as creating factory newspapers and letting workers participate, to some degree, in management — in short, trying to create a community in each place of work.

The early and mid-1930s, on the other hand, saw a flip in the other direction to differentiation, and this time, as the kids say, they went hard. They began with the ideals of "socialist competition," in which anything from individual workers to brigades to entire factories were expected to challenge one another to beat one another's production, leading to ever-higher numbers and successful rapid industrialization, and to some degree all of society was expected to beat its own production, as exemplified in the slogan "The Five Year Plan in Four Years!" Similarly, starting in 1935 with the Donbass coal miner Aleksei Stakhanov, the Soviet state began to single out and fete unusually productive workers with cash prizes, material rewards, media attention, and support for their exorbitant production during their shifts.

There were some problems with this, to put it lightly. Eventually, as we are now learning with catastrophic consequences in debates over sustainability, numbers just can't be pumped any higher. Over time, socialist competition created an atmosphere of tension and overwork, and failure to meet what soon became impossibly high challenges led to a general perception of insufficient socialist zeal, accusations of loafing, and even claims of sabotage. Stakhanovism, meanwhile, often led to resentment of so-called Stakhanovites, both because of their lavish treatment, and also because all the other workers were expected to help them maintain such ridiculously high quotas, which they felt hurt both their individual job satisfaction and their communal production.

I am not as well-versed in the exact way that things worked in the later Soviet Union, but I can say something about the general pattern. Later in Stalin's life, Soviet authorities eventually realized the counterproductive results of socialist competition and the Stakhanovite incentive system and pulled back from its excesses. However, for more or less the rest of the Soviet Union's existence, some kind of wage differentiation, continued to exist as an incentive, alongside cash prizes and, in the somewhat more materially plentiful days of the Khrushchev and Brezhnev periods, the promise of better apartments and dachas, vacation tickets, and plentiful recreational opportunities in one's free time. However, it remained much easier to get these things through personal connections, and in a lot of cases, as has more or less always been the case in all societies, people did unpleasant jobs not because of positive incentives, but because of negative ones — they had to work, and they couldn't find anything else to do.

Dirty Jobs Down Under

I also want to finish things off with an example from my own area of real expertise, the Moscow Metro in the early 1930s, because it lets us see a lot of these things in practice. Metro work was an extremely tough job, just like any kind of mining or construction, and in the early days of roughly 1931-1933, it was at its absolute most difficult, dangerous, and unpleasant. There was no machinery, no trucks, no hydraulic drills, and not even much technical expertise, so cave-ins, floods, and fires were sadly not uncommon. The things you'll read Western historians saying in the 1950s and 1960s about these untold numbers of gaunt workers slaving away on Stalin's vanity project are salaciously and insultingly exaggerated — and I could write a whole answer about that too — but the point is, even without the rather vulgar and orientalizing tales of toiling underclasses, work wasn't pleasant.

So how did the Soviet state convince people to work on the Metro? Coercion was undeniably part of it, but not the only way, or even the most common way, depending on what phase of work we're talking about. Forced laborers, mainly prisoners convicted of petty "wrecking" and appropriated by Metrostroi, were indeed employed on the Metro, although their lack of agency wasn't made explicit in the propaganda of the Metro, and according to William Wolf's doctoral monograph, even non-public archival sources don't say how many there were. However, as the project grew in importance, the number of volunteers swelled.

Many of the volunteer workers were cajoled into Metro work, or given a falsely rosy picture of what it would entail, but there was clearly a fair degree of enthusiasm for it as well. Some workers were recruited from places as far-flung as the Caucasus, Siberia, the Far East, and Bashkiria, and there were three increasingly large levies of young adult Komsomol members over the spring and summer of 1933, each of which undershot its target numbers. Metrostroi steadily increased its target strength, and reached a plateau of 70,000 workers and engineers by 1935, but for much of its existence it was desperately understaffed and understrength, by a half or even two thirds of its intended workforce, so this was not a job everybody was jumping to do. Some of them were certainly less than willing, or sold a lie, but the majority do seem to have genuinely seen Metro work as appealing for some reason.

For many of them, to be sure, it would have been a Hobson's choice between poverty in the countryside and Metro work. The countryside was overpopulated, underfed, and had largely been the loser in the collectivization campaign that had begun in 1929, as traditional ways of agriculture were reformed away and surpluses once again seized as they had been before the NEP. The city promised escape. ​Many Metro workers followed the old routes of seasonal migration that they and their parents had taken to work in Moscow since Witte's industrialization drive in the 1890s, with the exception that they made the move permanent this time. Similarly, they generally abided by existing social networks, following relatives or friends who had already made the journey, and finding both work and housing with their assistance. So although no decision made with the threat of poverty and starvation hanging over your head can ever truly be voluntary, the people who ​came to work on the Metro in the early 1930s did so no less voluntarily than in times of urbanization anywhere else.