 Shortly thereafter, on 1 December 1918, Prince Regent Alexander of Serbia proclaimed the existence of the Kingdom of Serbs, Croats, and Slovenes which was recognized by Belgrade and the National Council in Zagreb on the 28th and 29 December.Vladimir Dvorniković, a famous philosopher, advocated the establishment of a Yugoslav ethnicity in his 1939 book entitled "The Characterology of the Yugoslavs".His views included eugenics and cultural blending to create one, strong Yugoslav nation.