At the Great National Assembly of Serbs, Bunjevci and other Slavs from Bačka, Banat and Baranja, held in Novi Sad on November 25, 1918, the Rusyns were among ethnic groups who took part. Historiography states that among 757 attendees, 21 were Rusyn. Owing to their participation in the Great National Assembly, this small Slavic national community (in 1921, there were 12071 of them living in Bačka) made its contribution to the unification of the territories of the future province of Vojvodina with the Kingdom of Serbia. The author of this paper, on the basis of archival materials that remained unknown until now, aims to illustrate the circumstances of the arrival of the Rusyns to the Great National Assembly in 1918. Their delegates came from the municipalities of Ruski Krstur, Kucur, Stari Vrbas, Đurđevo and Novi Sad. Apart from Krstur, the Rusyns of Bačka lived together with people of other nationalities and religions, and the election of assembly members reflected the national distribution of the population in these towns and communities. Đurđevo was seat to a joint Serbian-Rusyn local council (this was an institution of the transitory government at the time of the collapse of Austria-Hungary) which organized the election of the assembly members. In Kucura, where the Rusyns were the majority population, the selected delegates included three Rusyns, a Hungarian and a German delegate. The multinational population of these Vojvodina towns showed solidarity even at times of political crises, acting as a unified political community. Among the most renowned members of the Great National Assembly was also a Greek Catholic priest from Novi Sad by the name of Jovan Hranilović (1855-1924). This poet, journalist and politician of Yugoslav persuasion left a notable mark on the cultural and social life of Novi Sad. Hranilović opened the Great National Assembly and acted as one of its chairmen. The author of this paper shows that Hranilović in fact represented the Rusyns at the Great National Assembly and that he was their champion and their organizer. He worked for several decades as a Rusyn priest in Novi Sad, an archdeacon in the Greek Catholic eparchy of Križevci for Bačka and Syrmia. To this day, researchers were unaware of the fact that Hranilović was elected as a member of the Assembly on November 23, at the assembly of the Rusyns from Novi Sad. This fact, along with numerous others, disputes a widely held belief that the Greek Catholic clergy among Rusyns were against the unification with the Kingdom of Serbia.