Milka Planinc, who has died aged 85, was a leading Croatian communist who served as prime minister of Yugoslavia between 1982 and 1986. Planinc's career took off during the "Croatian Spring", a political turmoil of the late 1960s and early 70s which shook Croatia, and the rest of Yugoslavia. She opposed the Croatian party leadership's calls for greater autonomy for Croatia, and its flirtation with Croat nationalists. The latter included Franjo Tudjman, who would become president of Croatia in 1990, as Yugoslavia was unravelling.
Tudjman and other nationalist dissidents were arrested, while the Croat party leadership was sacked by the president, Josip Broz Tito, in late 1971. Planinc was appointed head of the central committee of the league of communists of Croatia. She held the post until 1982, when she was appointed president of the federal executive council (socialist Yugoslavia's government), becoming the first woman to hold the post of prime minister in a communist country.
The appointment took place two years after Tito's death, when political unrest that started among ethnic Albanians in Kosovo in 1981 was, for the time being, overshadowed by an economic crisis. With Yugoslavia heavily in debt, the Planinc government accepted an IMF loan, but tight repayment deadlines undermined the government's position. Planinc, hitherto considered a conservative Titoist, was now among reformers, and was confronted by both conservatives and increasingly self-seeking republican leaderships. Her measures of austerity stabilised Yugoslavia's economy.
Although the programme of "economic stabilisation" hit ordinary Yugoslavs hard – they had been accustomed to a relatively high standard of living under Tito – Planinc remained popular. A traditional, male-dominated society respected a strong woman leader, especially as Planinc provided a sharp contrast with the increasingly ineffective rotating collective presidency that succeeded Tito. She was in some respects Yugoslavia's own "Iron Lady" and, like Margaret Thatcher, she was brought down by her party colleagues.
Planinc clashed with republican party leaders and eventually had to stand down in 1986. This symbolised the defeat of federal institutions in their power struggle with the republics, and marked the beginning of Yugoslavia's final phase. That same year Slobodan Milosevic emerged in Serbia and Milan Kucan in Slovenia. In Planinc's native Croatia, Stipe Suvar and Ivica Racan represented the younger forces, but they would be sidelined a few years later by Tudjman. While Racan remained in politics after the collapse of Yugoslavia and returned to power as prime minister of Croatia in 2000-03, Planinc and Suvar, who never abandoned their Yugoslav and communist ideals, were consigned to the margins of independent Croatia.
Born Milka Malada, in the small Dalmatian town of Drnis, she grew up during the period when the Yugoslav state actively promoted a unified Yugoslav identity. Formerly part of Austria-Hungary, Drnis had had a mixed Croat, Serb and Muslim population, but had been under Italian occupation at the end of the first world war. The town became part of the newly formed Kingdom of Serbs, Croats and Slovenes (as Yugoslavia was called between 1918 and 1929) following the 1920 Treaty of Rapallo. Young Milka, herself of a mixed Croat-Serb background, joined Tito's pan-Yugoslav communist-led resistance in 1941. Three years later she became a member of the Communist party of Yugoslavia and by the end of the war had earned several decorations and the rank of lieutenant in Tito's partisan army.
After the war, she studied at a management school in Zagreb and held several non-political jobs before being appointed head of an agitprop (ideological propaganda) committee in Zagreb in 1949. The following year she married a civil engineer, Zvonko Planinc, with whom she had a son and a daughter. Over the next decade and a half she gradually moved up the ranks to become Croatia's education minister in 1965.
In 1998 Planinc, discussing her period as prime minister with Dejan Jovic, author of Yugoslavia: A State That Withered Away (2009) and one of few scholars she talked to, said: "The party was supposed to be a cohesive force, but by then it had become ... the main source of conflicts and conservatism ... In Tito's time changes were still possible if Tito was convinced they were necessary. But after him ... [t]here was no money any more to satisfy everyone's needs. And the federal government had no instruments to run affairs on its own. It had to rely on the [constituent Yugoslav] republics, on the federal presidency, and on the party presidency. When members of the [republican] party leaderships became the main defenders of their own republics, Yugoslav cohesion became impossible."
Yugoslavia's collapse and the Croat-Serb war of the first half of the 1990s came as a hard blow to Planinc, who had dedicated her life to fighting for and building a socialist Yugoslavia. Her husband died in 1993, and her son, Zoran, killed himself the following year. Her health deteriorated: in addition to diabetes and heart problems, she suffered from cancer during the last years of her life. Once the most powerful woman in Yugoslavia, Planinc lived modestly in a small apartment in Zagreb, wheelchair-bound and looked after by her daughter, Vesna, who survives her. Planinc rarely spoke publicly during the past 20 years, going into a self-imposed near isolation. Those few she remained in contact with admired her dignity and principles.
Planinc's mind remained sharp. She had been working on political memoirs which remain uncompleted. But the recollections that she leaves behind promise to offer an invaluable insight into the history of Yugoslavia through the eyes of one of its leaders, whose rise and fall mirrored that of her country.
• Milka Planinc, politician, born 21 November 1924; died 7 October 2010