Principality of Reuss-Gera

The territories of four separate branches of the Junior Line amalgamated between 1824 and 1848, at which time the seniormost line of Gera retained sovereignty over the surviving cadet branches, which retained succession rights to the princely throne.[1] In 1905, the principality of Reuss Junior Line had an area of 827 km² (319 square miles) and a population of 145,000, with Gera as its capital.

In the aftermath of World War I, the territory of the Junior Line merged with that of the Elder Line in 1919 as the People's State of Reuss, which became part of the new state of Thuringia on 1 May 1920.

The House of Reuss practises a unique system of naming and numbering the male members of the family, every one of whom for centuries has borne the name "Heinrich", followed by a Roman numeral.[1] While most royal and noble houses assign a regnal number only to the ruling head of the house, and that in the sequential order of their reigns, the Reuss Junior Line ("Reuss, J.L.") used a numbering sequence for all male family members which began afresh with the first son born in each century. The male children within a single nuclear family need not bear sequential numbers, as all members of the larger family share the common numbering system. For example, the sons of Prince Heinrich LXVII Reuss of Schleiz, in order of their births, were named Heinrich V, Heinrich VIII, Heinrich XI, Heinrich XIV, and Heinrich XVI, with their male-line kinsmen holding the numerals in between according to the order of their births. In consequence of this naming system, certain heads of the Reuss Junior Line have had the highest numbers attached to their name of any European ruling families. The designation of "Junior Line" was dropped in 1930; the Elder Line ("Reuss, A.L.") had become extinct as its last male member, Heinrich XXIV, renounced his rights as sovereign in 1918 and died unmarried in 1927.[1]

A notable member of this family, Augusta Reuss-Ebersdorf (1757–1831), became the maternal grandmother of Queen Victoria of the United Kingdom.

One of the younger sub-lines of the branch which ruled the Reuss, J.L. until 1918, includes the "Counts of Plauen" from the late 19th century. When Prince Heinrich XXVI Reuss (1857-1913) married Countess Viktoria von Fürstenstein (1863-1949) in 1885, under the strict marriage rules then enforced by the Reuss dynasty, although he was but a younger son of a minor ruling family, their children were not allowed to bear the dynasty's princely title. They were, instead, designated "Counts of Plauen", although they remained in the line of succession to the two thrones of Reuss[1] The Fürstensteins lacked Uradel status: Viktoria's paternal grandfather, Pierre-Alexandre Le Camus (1774-1824), son of a minor noble French notary living in Martinique, rose to become foreign minister in Jerome Bonaparte's Kingdom of Westphalia, was ennobled there in 1807 and made a count of the French Empire in 1817).[2]

When the German Empire collapsed at the end of World War I, the reigning Prince Reuss lost his crown along with all the other monarchs whose realms were within Germany. In 1927, Henrich XXVI's son, known as Count Heinrich Harry of Plauen (1890-1951), was adopted by his childless uncle, Prince Heinrich XXX (1864-1939), and the now-deposed dynasty agreed to accept him as "Prince Heinrich Harry Reuß", along with those of his male-line descendants born of unions complying with the family's 1902 rules that permitted marriages to countesses (Heinrich Harry's wife, Huberta von Tiele-Winckler was only a baroness in her own right, but belonged to a family of comital rank in Prussia).[1] Their son Heinrich Enzio was thus accepted by the House of Reuss as a prince, but his own marriage to Baron Gustaf Peyron's daughter in 1949 occurred before the Reuss family conference of 1957 which lowered the marital standard again,[1] allowing dynastic inter-marriage with baronial families.

Strictly, therefore, since 1996 the House of Reuss recognized Prince Heinrich Ruzzo Reuss by that title, but without official membership in the dynasty or entitlement to the traditional style of Serene Highness,[1] while in German law the title is allowed since 1919 only as part of the surname, thus "Heinrich Ruzzo Prinz Reuss".

• Princess Augusta Reuss of Köstritz (1822–1862)
• Prince Heinrich XXIV Reuss of Köstritz (1855–1910), composer
• Princess Eleonore Reuss of Köstritz (1860–1917), Tsaritsa of Bulgaria
• Prince Heinrich XXXII Reuss of Köstritz, heir presumptive to Wilhelmina of the Netherlands until 1909
• Princess Magdalena Reuss of Köstritz, wife of Prince Hubertus of Prussia