Grand duke in the context of "King"

Karl August, sometimes anglicised as Charles Augustus (3 September 1757 – 14 June 1828), was the sovereign Duke of Saxe-Weimar and of Saxe-Eisenach (in personal union) from 1758, Duke of Saxe-Weimar-Eisenach from its creation (as a political union) in 1809, and grand duke from 1815 until his death. He is noted for the intellectual brilliance of his court.

Archduke (feminine: archduchess; German: Erzherzog, feminine form: Erzherzogin) was the title borne from 1358 by the Habsburg rulers of the Archduchy of Austria, and later by all senior members of that dynasty. It denotes a rank within the former Holy Roman Empire (962–1806), which was below that of emperor, and roughly equal to that of king, prince-(arch)bishop, and grand duke, but above that of sovereign prince and duke.

The territory ruled by an archduke or archduchess was called an archduchy. All remaining archduchies ceased to exist in 1918. The current head of the House of Habsburg is Karl Habsburg.

A royal family is the immediate family of monarchs and sometimes their extended family.

The term imperial family appropriately describes the family of an emperor or empress, and the term papal family describes the family of a pope, while the terms baronial family, comital family, ducal family, archducal family, grand ducal family, or princely family are more appropriate to describe, respectively, the relatives of a reigning baron, count/earl, duke, archduke, grand duke, or prince.

Traditional rank amongst European imperiality, royalty, peers, and nobility is rooted in Late Antiquity and the Middle Ages. Although they vary over time and among geographic regions (for example, one region's prince might be equal to another's grand duke), the following is a reasonably comprehensive list that provides information on both general ranks and specific differences. Distinction should be made between reigning (or formerly reigning) families and the nobility – the latter being a social class subject to and created by the former.

A grand duchy is a country or territory whose official head of state or ruler is a monarch bearing the title of grand duke or grand duchess.

Prior to the early 1800s, the only Grand duchy in Europe was located in what is now Italy: Tuscany (declared in 1569). During the 19th century there were as many as 14 grand duchies in Europe at once, some of which were revived after the Napoleonic Empire. Some of these were sovereign and nominally independent (Baden, Hesse and by Rhine, Mecklenburg-Schwerin, Mecklenburg-Strelitz, Oldenburg, Saxe-Weimar-Eisenach and Tuscany), some sovereign but held in personal union with larger realms by a monarch whose grand-dukedom was borne as a subsidiary title (Finland, Luxembourg, Transylvania), some of which were client states of a more powerful realm (Cleves and Berg), and some whose territorial boundaries were nominal and the position purely titular (Frankfurt).

A prince is a male ruler (ranked below a king, grand prince, and grand duke) or a male member of a monarch's or former monarch's family. Prince is also a title of nobility (often highest), often hereditary, in some European states. The female equivalent is a princess. The English word derives, via the French word prince, from the Latin noun prīnceps, from primus (first) and caput (head), meaning "the first, foremost, the chief, most distinguished, noble ruler, prince".

In a related sense, now not commonly used, all more or less sovereign rulers over a state, including kings, were "princes" in the language of international politics. They normally had another title, for example king or duke. Many of these were Princes of the Holy Roman Empire.

Duke is a male title either of a monarch ruling over a duchy, or of a member of royalty, or nobility. As rulers, dukes are ranked below emperors, kings, grand princes, grand dukes, and above sovereign princes. As royalty or nobility, they are ranked below grand dukes and above or below princes, depending on the country or specific title. The title comes from French duc, itself from the Latin dux, 'leader', a term used in republican Rome to refer to a military commander without an official rank (particularly one of Germanic or Celtic origin), and later coming to mean the leading military commander of a province. In most countries, the word duchess is the female equivalent.

Following the reforms of the emperor Diocletian (which separated the civilian and military administrations of the Roman provinces), a dux became the military commander in each province. The title dux, Hellenised to doux, survived in the Eastern Roman Empire where it continued in several contexts, signifying a rank equivalent to a captain or general. Later on, in the 11th century, the title Megas Doux was introduced for the post of commander-in-chief of the entire navy.

Prince Domnitor, in full Principe Domnitor (Romanian pl. Principi Domnitori) was the official title of the ruler of Romania between 1862 and 1881. It was usually translated as "prince regnant" in English and most other languages, and less often as "grand duke". "Domnitor" is an adjective derived from the Romanian word "domn" (lord or ruler) and, in turn, from the Latin "Dominus". The title Domn had been in use since the Middle Ages and it is also the Romanian equivalent to the Slavic Hospodar. Moldavian and Wallachian rulers had used this term for their title of authority as the head of state, while "voievod" represented the military rank as the head of the army.

The title acquired an officially recognized meaning after Moldavia and Wallachia united to form the Romanian United Principalities under Alexander John I, who had become the ruler of both states since 1859. Alexander John abdicated in 1866 and was succeeded by Carol I, who promulgated the first constitution who officially used the name Romania for the country. He held the title until 1881. When Romania was proclaimed a kingdom in March 1881, Carol became its first king.