There were three rulers known as Frederick (German Friedrich) III of Germany:

• Frederick the Handsome, Duke of Austria from 1308 to 1330, who was elected as German King in the time of Louis the Bavarian (1326) as the result of a compromise between the Houses of Wittelsbach and Habsburg. In this function he is Frederick III of Germany. However, since he predeceased Louis, he never went on to rule as Emperor.
• Emperor Frederick III from the House of Habsburg (Frederick V as Archduke of Austria), who, as German King (elected in 1440), was crowned as Holy Roman Emperor Frederick III in 1452.
• Emperor Frederick III, from the House of Hohenzollern, King of Prussia and German Emperor only for a few months in 1888. Technically, he should have been Emperor Frederick I, and had considered taking the name "Frederick IV" to show his status as heir of the Holy Roman Emperors; but since the Hohenzollern Emperors were numbered in continuation of the Kings of Prussia, he is also remembered as Frederick III.

There were at least three rulers of other countries known as Frederick III: Frederick the Handsome (born 1286; died January 13, 1330), from the House of Habsburg, was Duke of Austria as Frederick I and King of the Romans as Frederick (III). ... Events Henry VII is elected as king of the Holy Roman Empire. ... Events The Bulgars under Michael III are beaten by the Serbs at Velbuzhd, and large parts of Bulgaria fall to Serbia. ... The title King of the Romans (Latin: Rex Romanorum) — not to be confused with the early, partially mythical Kings of Rome — was carried by Holy Roman Emperors after they had been confirmed as Emperor, but before they had undergone the ceremony of coronation by the Pope. ... The last true Carolingian ruler of the east Franks, Louis the Child (893-911) was the son of the Emperor Arnulf of Carinthia. ... Events Change of emperor of the Ottoman Empire from Osman I (1299-1326) to Orhan I (1326-1359) Aradia de Toscano, is initiated into a Dianic cult of Italian Witchcraft (Stregheria), and discovers through a vision that she is the human incarnation of the goddess Aradia. ... The Wittelsbach family were the ruling dynasty of the German kingdom of Bavaria from 1180 to 1918 and of the Rhine Palatinate from 1214 until 1805; in 1815 the latter territory was incorporated into Bavaria, which had been a kingdom since 1806. ... Habsburg (sometimes spelled Hapsburg, but never so in official use) was one of the major ruling houses of Europe. ... Detail of Aeneas Piccolomini Introduces Eleonora of Portugal to Frederick III by Pinturicchio (1454-1513) Frederick III of Habsburg (born September 21 in Innsbruck, 1415; died August 19, 1493 in Linz) was elected as German King as the successor of Albert II in 1440. ... Habsburg (sometimes spelled Hapsburg, but never so in official use) was one of the major ruling houses of Europe. ... For alternative meanings, see number 1440. ... The Holy Roman Emperor was, with some variation, the ruler of the Holy Roman Empire, the predecessor of modern Germany, during its existence from the 10th century until its collapse in 1806. ... Events October - English troops under John Talbot, 1st Earl of Shrewsbury, land in Guyenne, France, and retake most of the province without a fight. ... Friedrich III of Germany. ... Aerial view of the castle, Hohenzollern, Germany. ... The coat of arms of the Kingdom of Prussia, 1701-1918 The word Prussia (German: Preußen or Preussen, Polish: Prusy, Lithuanian: PrÅ«sai, Latin: Borussia) has had various (often contradictory) meanings: The land of the Baltic Prussians (in what is now parts of southern Lithuania, the Kaliningrad exclave of... The term German Empire (Deutsches Reich) commonly refers to Germany, from its consolidation as a unified nation-state on January 18, 1871, until the abdication of Kaiser (Emperor) Wilhelm II on November 9, 1918. ... 1888 is a leap year starting on Sunday (click on link for calendar). ...

• Frederick III of Denmark
• Frederick III of Sicily, who is also known Frederick II of Sicily.
• Frederick III the Simple, who was really the third man of that name to occupy the Sicilian throne. See either article for an explanation of the anomaly.