This is one of the most famous Croatian tragic love stories. It involves Count Petar of Zren and his wife Katarina. Petar of Zren was an outstanding statesman and writer, his wife Katarina, a poet and a sister of Fran Kristo Frankopan. While the Croatian-Hungarian kingdom was under the Habsburg monarchy, disappointment with Habsburg rule grew in Croatia. Petar and Fran Kristo had great success in liberating areas occupied by the Turks: however, the Viennese Military council, instead of supporting the liberation of Hungarian and Croatian land, signed a shameful peace treaty with the Turks (known as the Warsaw Peace) by which the freed territories had to be handed back to the them. Disappointed Croatian and Hungarian nobility started a rebellion against the Habsburgs. Katarina, Fran Kristo and Petar started a secret plot which involved the French monarchy, Turks and Venice. The rebellion was unsuccessful and resulted in the cruel public decapitation of Petar and Fran Kristo in Wiener Neustadt near Vienna in 1671. The remains of these two Croatian martyrs were buried in the Cathedral of Zagreb in 1919. Katarina was imprisoned by general Spankau in a monastery in Graz, where she went insane and died in extreme poverty two years after Petar. Even the son of Peter and Katarina – Ivan Antun, the last of the Zrens – was imprisoned in Graz, solely because he belonged to this outstanding noble family. He died of pneumonia after 20 years of imprisonment in Schlossberg in Graz. This six-century old noble family died out, and their property was robbed. It should be stressed out that Petar and Fran went to Vienna voluntarily, having been promised a pardon, but were instead arrested and put to trial. During the trial they defended themselves, claiming that only the Croatian Parliament (Hrvatski Sabor) could trial them.