After the outbreak of the Great War he remained in Warsaw and in 1917 Kakowski was appointed to be a member of the Regency Council, a semi-independent and temporary highest authority of the Kingdom of Poland, recreated by the Central Powers as part of their Mitteleuropa plan.
Along with Czesław Miłosz, Danilo Kiš and György Konrád, he was sometimes classified into the literature of "Mitteleuropa"—dark and contemplative, yet humanistic and thought-provoking.