In 1391, during the administration of the Kingdom of Hungary, settlement named Szent Király (Sveti Kralj) was mentioned at this location.

After Maria Theresa of Austria assumed the throne in 1740, she encouraged vigorous colonization on crown lands, first of the Military Frontier and then of the entire nearby area, whose original Serb population had been decimated following the Great Turkish War.

In 1763, the Imperial Advisor Anton von Cothmann, proposed to his Empress Theresia that Kernei and the surrounding territory should be settled.

In the following decades the number of settlers increased yearly, reaching 291 families arriving in Kernjaja between 1794/1796, among them 83% Germans, 11% Hungarians and 6% Bohemians.

In December 1944, 340 young men and women were forcibly enslaved as war reparations to the Soviet Union to work in labor camps.

[1] The antifascist council for the liberation of Yugoslavia (AVNOJ) declared its mainly Danube Swabian population German public enemies and voided their citizenship and all civil rights.

After World War II, Krnjaja became part of the new Socialist Yugoslavia, within the People's Republic of Serbia and the Autonomous Province of Vojvodina.

In this time, Serbs from Croatia (Lika, Gorski Kotar, Žumberak, and Kordun) began living in the abandoned, expropriated buildings in the village.

The current name of the village, Kljajićevo, was introduced in 1949 and derives from Miloš Kljajić, a popular hero who was born in Kordun and was killed in Žumberak in 1944.

The streets are still lined with the acacia trees planted by the Shwovish settlers, and they bloom in magnificent profusion in the spring.