How did Solidarity perform in Poland’s 1989 general election?

In the June 1989 general election, which followed the legalization of the Solidarity trade union, the movement achieved a decisive victory in the first partially free elections held in a Soviet-bloc nation in over 40 years.12

Solidarity's performance in the election was as follows:

• Senate (upper house): Candidates endorsed by Solidarity won 99 of the 100 available seats.1
• Sejm (lower house): Solidarity won all 161 seats that were open to opposition candidates, out of a total of 460 seats.12

This overwhelming success paved the way for the formation of a coalition government in August 1989, led by Tadeusz Mazowiecki, who became the first noncommunist premier in Poland since the late 1940s.13