In a nutshell, it was a watershed of many movements, most of them striving for occupational autonomy within the central planning system. The system of occupations and professions established under the central planning regime is absolutely crucial to understand the dynamics of the entire post-war development in that country.
Since the country was predominantly rural until the 2nd world war (about 70% of population), sustained heavy human losses during the war (about 1/3 of the population, concentrated in cities) - the technical cadre immediately after the war was virtually non-existent. One of the top priorities of of the post-war policies was to provide suffcient technical cadre (the intelligentsia) and skilled industrial labor. These two groups are almost an exclusive creation of socialist educational policies (a system of voctaional and technical schools, as well as universities) - and also two major classes struggling for power. Th einterplay between these two classes can explain the dynamics of social movements in Poland.
Spontaneous worker-self management was essentially extinguished by the central planning authorities as early as 1947. The central planners opted for taylorist policies (micromanagement, speed-ups, piece-work rates), gutting the unions (the plant management de facto controlled them) by depriving them of two essential functions: collective bargaining (pay schedules were set centrally) and the right to strike. Wild-cat strikes were broken by dispatching security forces.
So during the initial period (esp. the 6-year plan (1949-55) plant managers had a clear upper hand vis a vis blue collar labor - but their own prerogatives were also curtailed by the micromanagement of the central planning. Since the 6-year plan failed to accomplish its objectives - the whole planning design (heavily centralised after the Soviet model) came under numerous criticisms, especially from plant management who sought greater occupational autonomy. That forged a temporary alliance between managers and the worker-self management movement that led to what is known as the Polish October in 1956 - an outbreak of riots followed by a set of relatively substantial institutional reforms of central planning (the stated goal was the introduction of market economy more or less along Keynesian lines).
At that time, blue collar gained substantial self-management through workers' councils, that were gradually dismantled during the next two or three years.
This is eseentially the model for the power struggle in Poland:
Stage 1: industrial management vies for control and autonomy with central planning autorities and the politbureau;
Stage 2: a crisis develops that calls for institutional reforms;
Stage 3: industrial mamangers and reformist elements within the central apparatus form alliances with other occupational groups, especially blue collar workers, but also professions to push for reforms;
Stage 4: institutional reform is introduced; all participating groups benefit;
Stage 5: the gains of the "allied" groups, especially blue collar workers and professions, are gradually taken away; thus leaving the industrial managers (plant and cartel level) the main beneficiaries.
This model is is repeated almost "verbatim" in 1980 - the formation of the "Solidarnosc" movement and in 1989.
The 1980 Solidarnosc was a watershed of various groups and interests, with the role of professions somewhat more visible than in 1956 (especially health care workers who objected to the crisis the public health care system that developed during 1970s) and blue collar being the most visible player. Initially, the reformist elements who acted as advisors set the movement's policy (e.g. my dad who was an exec in the shipyard industry was a Solidarnosc supporter, which BTW sent him to an involuntary early retirement after the 1981 crackdown, but at the same time he staunchly opposed the idea of workers' councils) -- and the union gained official recognition in November 1980. At that time many different groups jumped on the bandwagon, it was essentially a watershed of opposition against the government. The government and party leadership was replaced with a reformist faction (just like in 1956).
However, in 1981 more radical-left elements started gaining influence and the union adopted more and more militant stance, calling for what was dubbed as "active strike" which was defacto taking control of the plant operations by the workers' councils, and total bypassing formal management structures. Shortly after several chapters of Solidarnosc adopted resoltions advocating "active strike" - the "reformist" government imposed the martial law and banned the union altogether.
Another development that might have influenced that decision was that one Maggie Thatcher was busy breaking the miners union in the UK at that time, and used Poland as a "scab" by importing Polish coal. Continuous strikes in Poland (the mining region was one of the strongholds of Solidarnosc) threatened coal supply, and I am pretty sure that Maggie Thatcher (a folk hero among the Polish managerial class) and Wojtek Jaruzelski quickly reached a conclsion that something had to be done about it.
There is a certain tendency in the US to portray Solidarnosc as an essentially right wing movement - which is clearly a misconception. This was a genuine popular movement that had many ideological influences. Many technocrats were right-wingers (but more of the Thatcherite "strong-executive" variety, than the US religious right). Poland is a Catholic country, and you could also see a lot of Catholic symbolism, especially that it was very selectively highlighted by the Western media. Mind that people who spoke with Westerners were not workers but intellectuals who knew English, German or French, and were generally reactionary. Well, I was not a socialist back then either.
On the other hand, I also saw plenty of socialist references (for example quotations from Marx and Lenin) or anarcho-syndicalist ideals (e.g. workers' direct control of production). This populist element of the movement did not have a clearly articulated ideology - it was a mixture of patriotism, catholicism, and socialism -- a mixture you would find in popular movements in most Latin American countries, for example.
In 1989 another "managerial revolution" took place under the name of Solidarnosc, but this time this was mainly the technocrats positioning themselves for a plunder of the national economy. The left and labor elements of Solidarnsoc eventually re-emerged as a 'Labor Party" but it did not do well in the elections.
Wojtek