What country solidarity trade union was a strong 1990s political force?

The Solidarity trade union, known as "Solidarność" in Polish, was a significant political force in Poland during the 1990s. It emerged in the 1980s as a response to communist rule and played a crucial role in advocating for workers' rights and political change. Solidarity's influence helped pave the way for the end of communist governance in Poland and inspired similar movements across Eastern Europe. Its leader, Lech Wałęsa, later became the President of Poland, symbolizing the union's impact on the country's transition to democracy.