Ferdinand I of Romania in the context of "Alba Iulia"

Michael I (Romanian: Mihai I [miˈhaj]; 25 October 1921 – 5 December 2017) was the last king of Romania, reigning from 20 July 1927 to 8 June 1930 and again from 6 September 1940 until his forced abdication on 30 December 1947.

Shortly after Michael's birth, his father, Crown Prince Carol, had become involved in a controversial relationship with Magda Lupescu. In 1925, Carol was pressured to renounce his rights (in favour of his son Michael) to the throne and moved to Paris in exile with Lupescu. In July 1927, following the death of his grandfather Ferdinand I, Michael ascended the throne at age five, the youngest crowned head in Europe. As Michael was still a minor, a regency council was instituted, composed of his uncle Prince Nicolas, Patriarch Miron Cristea and Chief Justice Gheorghe Buzdugan. The council proved to be ineffective and, in 1930, Carol returned to Romania and replaced his son as monarch, reigning as Carol II. As a result, Michael returned to being heir apparent to the throne and was given the additional title of Grand Voievod of Alba-Iulia.

The Kingdom of Romania remained neutral throughout the first two years of World War I. They eventually entered the conflict on the side of the Entente from 27 August 1916 until insurmountable pressure from Central Powers - which had occupied two thirds of the country - led to an armistice being signed on 9 December 1917. Six months later, a crippling peace treaty was imposed on Romania, which the government ratified. King Ferdinand I refused to promulgate the treaty, hoping for an Allied victory on the Western Front. As the Central Power war efforts collapsed, Romania re-entered the war on 10 November 1918.

Romania was still a burgeoning state with great territorial ambitions at the onset of the war. It had achieved its independence following the Russo-Turkish War of 1877–1878, although millions of ethnic Romanians continued to reside outside the new nation's borders, particularly in Transylvania and Bessarabia, which were part of Austria-Hungary and Russia respectively. The Romanian monarchy, which was formed by members of the Hohenzollern dynasty, who were of Germanic origin, was sympathetic towards the cause of the Central Powers. The nation's political elite and the majority of the public favoured the Entente, as joining them would allow Romania to take Transylvania from Austria-Hungary, a region rich with natural resources and inhabited by a Romanian majority. Because of this social division and the general feeling that Romania still wasn't fully prepared for a war against a great power, the Romanians initially opted for neutrality.

The Romanian royal family (Romanian: Familia regală a României) constitutes the Romanian subbranch of the Swabian branch of the House of Hohenzollern (also known as the House of Hohenzollern-Sigmaringen), and was the ruling dynasty of the Kingdom of Romania, a constitutional monarchy in Central-Eastern Europe. The kingdom existed from 1881, when Carol I was proclaimed king, until 1947, when the last king, Michael I, was forced to abdicate and the Parliament proclaimed Romania a republic. Soon after, upon the establishment of the constitution of 13 April 1948, Romania became a people's republic, a state that lasted until the Romanian Revolution in 1989.

Current members of the former royal family include the daughters of the late, former King Michael of Romania. Some descendants have adopted the surname "of Romania". There are also descendants of Michael's older half-brother Carol Lambrino (also known as "Carol Hohenzollern" and "Carol Mircea Grigore of Romania" or, in Romanian, al României, on his amended, Romanian birth certificate), whose legitimacy was disputed and who were not recognised as royal during the reigns of Ferdinand, Carol II and Michael.

The coat of arms of Romania was adopted in the Romanian Parliament on 10 September 1992 as a representative coat of arms for Romania. The current coat of arms is based on the lesser coat of arms of interwar Kingdom of Romania (used between 1922 and 1947), which was designed in 1921 by the Transylvanian Hungarian heraldist József Sebestyén from Cluj, at the request of King Ferdinand I of Romania, it was redesigned by Victor Dima. As a central element, it shows a golden aquila holding a cross in its beak, and a mace and a sword in its claws. It also consists of the three colors (red, yellow, and blue) which represent the colors of the national flag. The coat of arms was augmented on 11 July 2016 to add a representation of the Steel Crown of Romania.

Carol II (15 October 1893 [O.S. 3 October 1893] – 4 April 1953) was King of Romania from 8 June 1930 following a coup that deposed his son until his forced abdication on 6 September 1940. As the eldest son of King Ferdinand I, he was crown prince from the death of his granduncle, King Carol I, in 1914 until he was forced to renounce his right to the throne in 1925.

Carol's life and reign were surrounded by controversy, such as his desertion from the army during World War I. Another controversy was his marriage to Zizi Lambrino, who was not from a royal lineage. After the dissolution of his first marriage, he met Princess Helen of Greece and Denmark, daughter of King Constantine I of Greece, married her in March 1921, and later that year, they had a son, Michael. Due to his continued extramarital affair with Elena Lupescu, Carol was forced to renounce his succession rights in 1925. His father removed Carol from the royal house of Romania and he was exiled to France along with Lupescu. Michael, aged 5, inherited the throne on the death of King Ferdinand in 1927. Princess Helen divorced Carol in 1928.

Prince Nicholas of Romania (Romanian: Principele Nicolae al României; 5 August 1903 – 9 June 1978), later known as Prince Nicholas of Hohenzollern-Sigmaringen, was the fourth child and second son of King Ferdinand I of Romania and his wife Queen Marie.

In 1927 after the death of his father, Nicholas was appointed as one of the three regents for his minor nephew King Michael I. His position as regent ended in 1930 with the return of his older brother Prince Carol to Romania to take over as King of Romania.

The Treaty of Bucharest (1918) was a peace treaty between Romania and the opposing Central Powers following the stalemate reached after the campaign of 1917. This left Romania isolated after Russia's unilateral exit from World War I (see the Armistice of Focșani and Treaty of Brest-Litovsk).

Following the Central Powers' ultimatum issued during the meeting [ro] between King Ferdinand I of Romania and Austro-Hungarian Foreign Minister Ottokar Czernin on 27 February [O.S. 14 February] 1918 at the Răcăciuni railway station, Ferdinand summoned a Crown Council [ro] on 2 March [O.S. 17 February] in Iași, the Romanian capital-in-exile. After long and difficult discussions, which lasted three days, and despite the strong opposition of Queen Marie and General Constantin Prezan, the Crown Council decided to accept the ultimatum and send envoys to Buftea to negotiate a preliminary peace treaty. The preliminary peace treaty was concluded on 5 March [O.S. 20 February] 1918, by which Romania agreed to border rectifications in favor of Austria-Hungary, to cede the whole of Dobruja to Bulgaria, to demobilize at least eight divisions, to evacuate the Austro-Hungarian territory still in its possession, and to allow the transport of Central Powers troops through Western Moldavia and Bessarabia towards Odessa.