Natalija was born in Trieste, Austria-Hungary on 10 October 1882, the daughter of Colonel Alexander Konstantinović and Milena Opuić, of Trieste. She was descended from the tragic, ill-fated Obrenović dynasty which had ruled Serbia for the greater part of the 19th century. She had one brother. Her paternal grandmother, Princess Anka Obrenović, was the niece of Miloš Obrenović I, Prince of Serbia, founder of the House of Obrenović. Natalija and her family were exiled from Serbia after her father criticised King Alexander I's unpopular marriage to the notorious Draga Mašin. They lived alternatively between Nice, Italy, and Vienna.
Marriages and issue
On 25 July 1902, at Cetinje, Natalija was married to Prince Mirko Petrović-Njegoš of Montenegro, Grand Duke of Grahovo and Zeta, the second eldest son of Nicholas I of Montenegro. Prince Mirko had allegedly fallen passionately in love with Natalija who was described as a beautiful, dark-eyed brunette. King Alexander was not pleased by the news of their marriage, as he believed Mirko had only married her in order to obtain the Serbian crown; in addition, Mirko's dead elder sister, Zorka had been the wife of Alexander's rival Peter Karađorđević. As a sign of his displeasure he refused to receive either Natalija or Mirko at his court. As Natalija was the granddaughter of Princess Anka Obrenović, who had been assassinated in Belgrade on 10 June 1868 along with her cousin, Mihailo Obrenović III, the Serbian government promised that in the event of King Alexander Obrenović dying childless, Mirko would be proclaimed Crown Prince of Serbia. Events, however, did not proceed as Nikola I of Montenegro had hoped. In late May 1903, King Alexander and his consort, Draga, were assassinated by a group of Army officers led by Captain Dragutin Dimitrijević Apis. Prior to the assassination, the conspirators had voted to pass the crown to Mirko's brother-in-law, Peter, the head of the rival Serbian dynasty, the Karađorđevićs. This was because the Karađorđevićs were allied with Russia, whereas the Obrenovićs were decidedly pro-Habsburg, and therefore distasteful to many Serbs in light of the fervent Pan-Slavic nationalism that had engulfed Serbia since the 19th century. In fact, Natalija's husband later joined the Black Hand secret society in 1911, and aspired to be its leader.
In 1908, her two eldest sons died, and she gave birth to her third son, Michael. On 28 August 1910, Montenegro became a kingdom, with her father-in-law ascending the Montenegrin throne as the first and only king. In 1916, the defence of Montenegro collapsed when the Austro-Hungarian forces invaded the kingdom during World War I, and the entire royal family, including Natalija, was compelled to flee to Italy. The couple were divorced in 1917, and Natalija moved to Paris with her surviving sons. The following year, Mirko died in Vienna and her eldest surviving son Michael became head of the House of Petrović-Njegoš and pretender to the defunct throne of Montenegro. Natilija took Michael to Eastbourne, England, where he completed his primary education. In March 1920, she married secondly in Eastbourne, Gaston Count Errembault de Dudzeele, a Belgian diplomat, and had two daughters:
Hélène Errembault de Dudzeele married in 1949, Philippe Hiolle. She had one daughter and one son : Caroline Hiolle and Hervé Hiolle.
Anne-Marie Errembault de Dudzeele married in 1946, Philippe Cerf, and in 1958, Pierre Saville. She had three daughters : Géraldine Cerf, Carlyne Cerf and Marie-Pierre Saville.
Princess Natalija died in Paris on 21 August 1950, at the age of 67.
