Carol I of Romania Carol I ( 20 April 1839 – 27 September ( O . S . ) / 10 October ( N . S . ) 1914 ) , born Prince Karl of Hohenzollern - Sigmaringen was the ruler of Romania from 1866 to 1914 . He was elected Ruling Prince ( Domnitor ) of the Romanian United Principalities on 20 April 1866 after the overthrow of Alexandru Ioan Cuza by a palace coup . After the defeat of the Ottoman Empire ( 1878 ) in the Russo - Turkish War , he declared Romania a sovereign nation ( the country had been under the nominal suzerainty of the Ottoman Empire until then ) . He was proclaimed King of Romania on . He was the first ruler of the Hohenzollern - Sigmaringen dynasty , which ruled the country until the proclamation of a republic in 1947 . During his reign , Carol I personally led Romanian troops during the Russo - Turkish War and assumed command of the Russo / Romanian army during the siege of Plevna . The country achieved full independence from the Ottoman Empire ( Treaty of Berlin , 1878 ) and acquired the Cadrilater from Bulgaria in 1913 . Domestic political life , still dominated by the country ' s wealthy landowning families organized around the rival Liberal and Conservative parties , was punctuated by two widespread peasant uprisings , in Wallachia ( the southern half of the country ) in April 1888 and in Moldavia ( the northern half ) in March 1907 . He married Elisabeth of Wied in Neuwied on 15 November 1869 . They only had one daughter , Maria , who died at the age of three . Carol never produced a male heir , leaving his elder brother Leopold next in line to the throne . In October 1880 Leopold renounced his right of succession in favour of his son William , who in turn surrendered his claim six years later in favour of his younger brother , the future king Ferdinand . Early life . Prince Karl Eitel Friedrich Zephyrinus Ludwig of Hohenzollern - Sigmaringen was born in Sigmaringen , the second son of Prince Karl Anton of Hohenzollern - Sigmaringen and his wife , Princess Josephine of Baden . After finishing his elementary studies , Karl entered the Cadet School in Münster . In 1857 he was attending the courses of the Artillery School in Berlin . Up to 1866 , when he accepted the crown of Romania , he was a Prussian officer . He took part in the Second Schleswig War , including the assault of the Fredericia citadel and Dybbøl , an experience which would be very useful to him later in the Russo - Turkish war . Although he was quite frail and not very tall , prince Karl was reported to be the perfect soldier , healthy and disciplined , and also a very good politician with liberal ideas . He was familiar with several European languages . His family being closely related to the Bonaparte family ( one of his grandmothers was a Beauharnais , Joséphine ' s niece - in - law , and the other a Murat , Joachim ' s niece Marie Antoinette Murat ) , they enjoyed very good relations with Napoleon III of France . Romania was at the time under the influence of French culture , and Napoleon ' s recommendation of Prince Karl of Hohenzollern - Sigmaringen weighed heavily with Romanian politicians of the time , as did his blood relation to the ruling Prussian family . Ion Brătianu was the Romanian politician who was sent to negotiate with Karl and his family the possibility of installing him on the Romanian throne . On the way to Romania . The former Romanian ruler , Alexandru Ioan Cuza , had been expelled from the country by the leading noblemen and Romania was in a political chaos . Cuza ' s double election , both in Wallachia and in Moldavia ) had been the basis on which the Romanian Principalities ' unification was recognized by the European powers . With him gone , the country was in danger of disintegration . Due to the political conflict between Prussia and the Austrian Empire , Karl travelled incognito by railroad from Düsseldorf to Budapest , under the name of Karl Hettingen . From Budapest he travelled by carriage , as there was no railroad to Romania . As he crossed the border onto Romanian soil , he was met by Brătianu , who bowed before him and asked Karl to join him in his carriage . On 10 May 1866 ( 22 May 1866 N . S . ) , Karl entered Bucharest . The news of his arrival had been transmitted by telegraph and he was welcomed by a huge crowd eager to see the new ruler . In Băneasa he was given the keys to the capital city . Eventually it was a rainy day after a long period of drought , apparently a very favorable sign . As he was crowned , Karl swore this oath : " I swear to guard the laws of Romania , to maintain the rights of its People and the integrity of its territory . " He spoke in French , as he did not speak Romanian . However , he endeared himself to his adopted country by adopting the Romanian spelling of his name , Carol . The Constitution . Immediately after arriving in the country , the Romanian parliament adopted , on 29 June 1866 , the 1866 Constitution of Romania , one of the most advanced constitutions in that time . This constitution allowed the development and modernization of the Romanian state . In a daring move , the Constitution chose to ignore the nominal suzerainty of the Ottoman Empire , which paved the way towards a full independence . Article 82 stated that " The ruler ' s powers are hereditary , starting directly from His Majesty , prince Carol I of Hohenzollern - Sigmaringen , on the male line through the right of first - born , with the exclusion of women and their issue . His Majesty ' s descendants will be raised in the Eastern Orthodox Religion . " In 1877 , Romania was proclaimed independent , making Carol fully sovereign over Romania . From 1878 , Carol held the title of Royal Highness ( " Alteță Regală " ) . On 15 March 1881 , the constitution was amended to proclaim Romania a kingdom . Carol became the first king , while the heir would be called Prince Royal . On 10 May , Carol was crowned king . A devoted King . King Carol was reported to be a cold person . He was permanently concerned with the prestige of the dynasty he had founded . His wife , Elizabeth , claimed he ' wore the crown in his sleep ' . He was very meticulous and he tried to impose his style upon everyone that surrounded him . Though he was devoted to his job as a Romanian prince and king , he never forgot his German roots . In 48 years of rule — far and away the longest in Romanian history — he helped Romania gain its independence , he raised its prestige , he helped redress its economy and he established a dynasty . In the Carpathian mountains , he built Peleş Castle , still one of Romania ' s most visited touristic attractions . The castle was built in German style , as a reminder of the king ' s origin . After the Russo - Turkish war , Romania gained Dobrogea and Carol ordered the first bridge over the Danube , between Fetești and Cernavodă , linking the newly acquired province to the rest of the country . As a member of the German higher landed aristocracy ( " Fürst " ) , Carol never managed to follow the much - needed liberal and poor - friendly policies initiated by his predecessor , Alexandru Ioan Cuza . Left unsolved , the grave social problems caused by the inequity of land ownership , ignited peasant uprisings throughout the reign of Carol I . The peasant class was suppressed during 1907 revolt , at the cost of 10 , 000 lives . Being under the influence of local landlords , the king failed to put together a sound administration , as envisioned by Prince Cuza . The end of the reign . The long rule of Carol helped the quick development of the Romanian state . But , towards the end of his reign and the start of the World War I , Carol wanted to enter the war on the side of the Central Powers . However , Romanian public opinion was overwhelmingly Francophile and sided with the Triple Entente . Carol had signed a secret treaty in 1883 which had linked Romania with the Triple Alliance ( 1882 ) . Although the treaty was to be activated only if Russia attacked one of the signatories , Carol was convinced that the honourable thing to do was to enter the war supporting the German Empire and his cousin , Emperor William II . In , an emergency meeting was held with the Crown Council , where Carol told them about the secret treaty and shared his opinion with them . However , most of the Crown Council members strongly disagreed , opting for neutrality . King Carol died in . The future King Ferdinand , under the influence of his wife , Marie of Edinburgh , a British princess , was more willing to listen to public opinion . Life and family . When he was elected prince of Romania , Carol was unmarried . In 1869 , the prince started a trip around Europe and mainly Germany , to find a bride . During this trip he met and married Princess Elizabeth of Wied at Neuwied on 15 November 1869 . Their marriage was one of the most unfit matches in history , with Carol being a cold and calculated man while Elizabeth was a notorious dreamer . They had one child , Princess Maria , born in 1871 , who died on the 24th of March 1874 . She had no prospect of inheriting her father ' s throne ; as mentioned above the Constitution limited succession to the male line . This led to the further estrangement of the royal couple , Elizabeth never completely recovering from the trauma of losing her only child . After the proclamation of the Kingdom ( 1881 ) , the succession was a very important matter of state . Since Carol ' s brother , Leopold , and his oldest son , William , declined their rights , the second son of Leopold , Ferdinand , was named prince of Romania and heir - presumptive to the throne . Towards the end of Carol ' s life , though , Carol and Elizabeth finally found a way to understand each other and were reported to have become good friends . Sources . Boris Crǎciun – " " Regii şi Reginele României " " , Editura Porţile Orientului , Iaşi