Born on August 20, 1930, Jan Olszewski was a defence attorney in political trials of oppositionists during communist times, notably in the 1960s and 1970s. In the 1980s, when the nationwide Solidarity movement emerged in defiance of the communist authorities, Olszewski became an advisor to what was the first independent trade union in the Soviet bloc and its leader Lech Wałęsa.
When communism collapsed in 1989, Olszewski became a political leader and later an advisor to late President Lech Kaczyński. He headed the Polish government in 1991-1992.
He was awarded the Order of the White Eagle, Poland's top distinction, in 2009.
"A great statesman, in the best sense of the word, a man who served Poland until the end," President Andrzej Duda said on Friday as he described Olszewski for PAP. "What was great about him was his readiness to serve, even when he became physically unfit, but he retained his full mental capacity until the last days of his life," Duda said.
"Jan Olszewski was a man that was totally honest and true to his beliefs, but also a very brave person. He proved his steadfastness on many occasions - first during WWII, later in communist times and then in democratic Poland," PM Mateusz Morawiecki wrote on Twitter.
"Poland has suffered a great loss. Jan Olszewski, an outstanding man, who made a strong contribution to independence, one of the leaders of the patriotic camp, has passed away. Rest in peace! Condolences to the Family and close ones," Jarosław Kaczyński, leader of the ruling Law and Justice (PiS), was quoted as saying by the party's spokesperson on Twitter.
Sejm (lower house) Speaker Marek Kuchciński in his Friday tweet called Olszewski "a great man and a true patriot."
Senate Speaker Stanisław Karczewski wrote on Twitter that Olszewski was "a unique man and politician who served Poland and Poles with courage and devotion."
US Ambassador to Poland Georgette Mosbacher in her Friday tweet stressed Olszewski's role as a defence attorney of anti-communist activists and an advocate of Poland's NATO membership.
European Council President Donald Tusk, a former Polish prime minister, described Olszewski on Twitter as "a brave defence attorney in political trials, a member of Solidarity and a good man."
Olszewski will receive a full state funeral, PM's Office head Michał Dworczyk told PAP. (PAP)