The Principality of Reuss-Gera (), called the Principality of the Reuss Junior Line () after 1848, was a sovereign state in modern Germany, ruled by members of the House of Reuss.<ref name="ghda">{{cite book | title=Genealogisches Handbuch des Adels, Fürstliche Häuser, Band XVI.|publisher= C.A. Starke Verlag | year=2001 | location=Glücksburg | chapter=Reuß |pages=127–128, 139–140, 592–593 | language=de| ISBN=978-3-7980-0824-3}}</ref> It was one of the successor states of the Imperial County of Reuss. The Counts Reuss, with their respective capitals and Residenzen at Gera, Schleiz, Lobenstein, Köstritz and Ebersdorf, were all elevated to the title of prince (Fürst) in 1806. Their successor branch heads shared that title, while their cadets were also each titled prince (Prinz). Thus all males of the family were properly "Prince Heinrich (Roman numeral) Reuss, J.L.", without use of a nobiliary particle, although for convenience their branch names remained in colloquial use (for example, "Prince Heinrich I Reuss of Köstritz"). Territory The territories of four separate branches of the Junior Line amalgamated between 1824 and 1848, at which time the senior branch of Gera retained sovereignty over the surviving cadet branches, which retained succession rights to the princely throne. In 1905, the principality of Reuss Junior Line had an area of 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 princely house 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. 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