Ernestine duchies in the context of "House of Saxe-Coburg and Gotha"

Saxe-Weimar (German: Sachsen-Weimar) was one of the Saxon duchies held by the Ernestine branch of the Wettin dynasty in present-day Thuringia. The chief town and capital was Weimar. The Weimar branch was the most genealogically senior extant branch of the House of Wettin.

Saxe-Eisenach (German: Sachsen-Eisenach) was an Ernestine duchy ruled by the Saxon House of Wettin. The state intermittently existed at three different times in the Thuringian region of the Holy Roman Empire. The chief town and capital of all three duchies was Eisenach.

Saxe-Weimar-Eisenach (German: Sachsen-Weimar-Eisenach) was a German state, created as a duchy in 1809 by the merger of the Ernestine duchies of Saxe-Weimar and Saxe-Eisenach, which had been in personal union since 1741. It was raised to a grand duchy in 1815 by resolution of the Congress of Vienna. In 1903, it officially changed its name to the Grand Duchy of Saxony (German: Großherzogtum Sachsen), but this name was rarely used. The grand duchy came to an end in the German Revolution of 1918–19 with the other monarchies of the German Empire. It was succeeded by the Free State of Saxe-Weimar-Eisenach, which was merged into the new State of Thuringia two years later.

The full grand ducal style was Grand Duke of Saxe-Weimar-Eisenach, Landgrave in Thuringia, Margrave of Meissen, Princely Count of Henneberg, Lord of Blankenhayn, Neustadt and Tautenburg.

Saxe-Coburg and Gotha (German: Sachsen-Coburg und Gotha), or Saxe-Coburg-Gotha (German: Sachsen-Coburg-Gotha [ˈzaksn̩ ˈkoːbʊʁk ˈɡoːta]), was an Ernestine duchy in Thuringia ruled by a branch of the House of Wettin, consisting of territories in the present-day states of Thuringia and Bavaria in Germany. It lasted from 1826 to 1918. In November 1918, Charles Edward, Duke of Saxe-Coburg and Gotha, was forced to abdicate. In 1920, the northern part of the duchy (since 1918 the Free State of Gotha; culturally and linguistically Thuringian) was merged with six other Thuringian free states to form the Free State of Thuringia: Saxe-Weimar-Eisenach (until 1918 a grand duchy), Saxe-Altenburg and Saxe-Meiningen (until 1918 duchies), Schwarzburg-Rudolstadt and Schwarzburg-Sondershausen (until 1918 principalities), as well as the People's State of Reuss (until 1918 the principalities of Reuss-Gera and Reuss-Greiz). The southern part of the duchy (since 1918 the Free State of Coburg; culturally and linguistically Franconian), as southernmost of the Thuringian states, was the only one which, after a referendum, became part of the Free State of Bavaria.

The name Saxe-Coburg-Gotha also refers to the family of the ruling House of Saxe-Coburg and Gotha, which played many varied roles in the dynastic and political history of Europe in the 19th and 20th centuries. In the early part of the 20th century, before the First World War, it was the family of the sovereigns of the United Kingdom, Belgium, Portugal, Bulgaria, and Saxe-Coburg-Gotha. In 1910, the Portuguese king was deposed, and the same thing occurred in Saxe-Coburg-Gotha in 1918 and in Bulgaria in 1946 (although effective control had already ceased two years prior due to a coup). As of 2025, a branch of the family still reigns in Belgium, and while the British line still technically exists up to the present day, it now uses the name Windsor due to a proclamation issued by King George V in 1917. The former Tsar of Bulgaria, Simeon II (reigned 1943–46), kept his surname while serving as the Prime Minister of Bulgaria from 2001 to 2005.

Saxe-Coburg-Saalfeld (German: Sachsen-Coburg-Saalfeld) was one of the Saxon Duchies held by the Ernestine line of the House of Wettin. Established in 1699, the Saxe-Coburg-Saalfield line lasted until the reshuffle of the Ernestine territories that occurred following the extinction of the Saxe-Gotha line in 1825, in which the Saxe-Coburg-Saalfeld line received Gotha, but lost Saalfeld to Saxe-Meiningen.

Saxe-Meiningen (/ˌsæks ˈmaɪnɪŋən/ SAKS MY-ning-ən; German: Sachsen-Meiningen [ˌzaksn̩ ˈmaɪnɪŋən]) was one of the Saxon duchies held by the Ernestine line of the House of Wettin, located in the southwest of the present-day German state of Thuringia.

Established in 1681, by partition of the Ernestine Duchy of Saxe-Gotha among the seven sons of deceased Duke Ernest the Pious, the Saxe-Meiningen line of the House of Wettin lasted until the end of the German monarchies in 1918.