The Frankish kingdom was split by the Treaty of Verdun in 843. The rulers of the eastern area thus called themselves rexFrancorum ("king of the Franks"), rex Francorum orientalium ("king of the East Franks"), and later just rex. A reference to the "Germans", indicating the emergence of a German nation of some sort, did not appear until the late 11th century, when the pope began to refer to his enemy Henry IV as rex teutonicorum (another exonym for Germans) in order to brand him as a foreigner. The kings reacted by consistently using the title rex Romanorum, king of the Romans, to emphasize their universal rule even before becoming emperor. This title remained until the end of the Empire in 1806, though after 1508 emperors-elect added "king in Germany" to their titles. In this and related entries, the kings and are called kings of Germany for clarity's sake.
The Kingdom of Germany was never entirely hereditary; rather, ancestry was only one of the factors that determined the succession of kings. During the 10th to 13th centuries, the king was formally elected by the leading nobility in the realm, continuing the Frankish tradition. Gradually the election became the privilege of a group of princes called electors, and the Golden Bull of 1356 formally defined election proceedings.
In the Middle Ages, the king did not assume the title "emperor" (from 982 the full title was Imperator Augustus Romanorum, Venerable Emperor of the Romans) until crowned by the pope. Moving to Italy, he was usually first crowned with the Iron Crown of Lombardy, after which he assumed the title of rex Italiae, king of Italy. After this, he would ride on to Rome and be crowned emperor by the pope.
Regnal numbers were not formally adopted until the late Middle Ages. Many of the early Frankish monarchs shared names and even nicknames. For example, Emperor Louis IV is enumerated after the three previous emperors named Louis, while King Louis IV is enumerated after the three previous kings named Louis, even though they were all members of the same family. Both German and French monarchs saw themselves as the successors of Charlemagne, hence why he and Louis the Pious, both emperors, are enumerated as "Charles I" and "Louis I" in both lists. Emperors beginning with Emperor Lothair III, who was actually the second emperor of that name, abandoned any distinction in numbering between his rule as king and his rule as emperor.
Maximilian I was the first king to bear the title of emperor-elect. After his march to Rome for his Imperial coronation failed in 1508, he had himself proclaimed emperor-elect with papal consent. His successor Charles V also assumed that title after his coronation in 1520 until he was crowned emperor by the pope in 1530. From Ferdinand I onwards, all emperors did not get crowned by the Pope anymore. At the same time, chosen successors of the emperors held the title of king of the Romans, if elected by the college of electors during their predecessor's lifetime.
The list is heavely intertwined with lists of Holy Roman Emperors and Austrian rulers until the 19th century. The German state of Prussia formally established Germany as a nation-state in 1871.
The title "King of the Romans", used in the Holy Roman Empire, denoted a ruler elected by the German princes whose authority was primarily exercised over the Germanic-speaking territories of the empire. While no formal “King of Germany” existed, the king’s election and governance effectively corresponded to that of a monarch over these lands. After election, the king would traditionally proceed to Rome to be crowned emperor by the pope.
4th in descent from Albert I; 2nd cousin of Albert II. His 53-year reign was the longest of any German monarch. Also ruled as duke of Inner Austria since 1424, amounting to a total reign of 69 years.
Grandson of Maximilian I; was also King of Spain, Archduke of Austria, and ruler of several other territories. Reigned over a massive empire, but abdicated and divided his realm before his death on 21 September 1558. Last Emperor to receive the imperial coronation from the Pope.
