the major defeat of May 22. Hatvany and most of his armed group were massacred by their adversaries, as Iancu captured their cannons, switching the tactical advantage for the next months. Hatvany's troops lost 5,000 soldiers and all of their artillery. Kossuth was angered by Hatvany's gesture (an inspection of the time dismissed all of Hatvany's close collaborators), especially since it made future negotiations unlikely. On 8 June, the Romanian stronghold in the mountains was attacked by the largest Hungarian force yet: 4,000 men supported by 19 cannons led by General . The battle lasted between 11 and 17 June and ended in a crushing victory for the Romanians, the Hungarians having at least 500 troops killed during the battle. The Russian intervention in June precipitated events, especially since Poles fighting in the Hungarian revolutionary contingents wanted to see an all-out resistance to the Tsarist armies. People like Henryk Dembiński mediated for an understanding between Kossuth and the Wallachian émigré revolutionaries. The latter, understandably close to Avram Iancu (especially Nicolae Bălcescu, Gheorghe Magheru, Alexandru G. Golescu, and Ion Ghica) were also keen to inflict a defeat on the Russian armies that had crushed their movement in September 1848. Fighting also continued in July, during the peace negotiations, on 2, 4, and 22 July, all Hungarian attacks being repulsed yet again. Finally, the conflict ended on 29 July, as Avram Iancu offered a guarantee to the Hungarian troops that he would not attack them, allowing them to withdraw in front of the Austro-Russian offensive. Negotiations Bălcescu and Kossuth met in May 1849, in Debrecen. The contact has for long been celebrated by Romanian Marxist historians and politicians: Karl Marx's condemnation of everything opposing Kossuth had led to any Romanian initiative being automatically considered "reactionary". In fact, it appears that the agreement was in no way a pact: Kossuth meant to flatter the Wallachians, by getting them to champion the idea of Iancu's armies leaving Transylvania for good, in order to help Bălcescu in Bucharest. While agreeing to mediate for peace, Bălcescu never presented these terms to the fighters in the Apuseni Mountains. His personal documents (commented by ) show that the un-realistic assumptions of Kossuth had made him view the Hungarian leader as a "demagogue". Even more contradictory, the only thing Avram Iancu agreed to (and which no party had asked for) was his forces' "neutrality" in the conflict between Russia