K. u. k.

The German phrase kaiserlich und königlich (pronounced [ˈkaɪzɐlɪç ʔʊnt ˈkøːnɪklɪç], Imperial and Royal), typically abbreviated as k. u. k., k. und k., k. & k. in German (in all cases the "und" is always spoken unabbreviated), cs. és k. (császári és királyi) in Hungarian, c. a k. (císařský a královský) in Czech, C. i K. (Cesarski i Królewski) in Polish, c. in k. (cesarski in kraljevski) in Slovenian, c. i kr. (carski i kraljevski) in Croatian, and I.R. (imperial regio) in Italian, refers to the Court of the Habsburgs in a broader historical perspective. Some modern authors restrict its use to the Dual Monarchy of Austria-Hungary from 1867 to 1918. During that period, it indicated that the Habsburg monarch reigned simultaneously as the Emperor of Austria and as the King of Hungary, while the two territories were joined in a real union (akin to a two-state federation in this instance). The acts of the common government, which only was responsible for the Imperial & Royal ("I&R") Ministry of Foreign Affairs, the I&R Ministry of War and the I&R Ministry of Finance (financing only the two other ministries), were carried out in the name of "His Imperial and Royal Majesty" and the central governmental bodies had their names prefixed with k. u. k.

Before 1867, the territories under the control of the Habsburg monarch in Vienna used kaiserlich und königlich or the hyphenated kaiserlich-königlich interchangeably. Neither of the spellings defined a hierarchy among the Habsburg dynastic kingdoms, principalities, duchies, and other bodies politic. The Habsburg monarchs ruled the kingdoms of Hungary, Croatia and Bohemia as their Kings. The title Emperor applied to their role as heads of the conglomerate of the mostly German states called the Holy Roman Empire until 1806. The same title, Emperor, came to identify their role as rulers of the newly named Austrian Empire that the Habsburgs attributed so from 11 August 1804.

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