Eugen Maximilianovich, 5th Duke of Leuchtenberg
Eugen Maximilianovich Romanowsky, 5th Duke of Leuchtenberg, Prince Romanowsky (8 February 1847 – 31 August 1901) was a son of Maximilian de Beauharnais, 3rd Duke of Leuchtenberg and Grand Duchess Maria Nikolaevna of Russia Duke of Leuchtenberg.
He succeeded his brother Nicholas Maximilianovich as Duke of Leuchtenberg from 1891 until his death.
Countess Elisabeth of Leuchtenberg
Elisabeth of Leuchtenberg( born: March 1537- died: 6 July 1579 in Dillenburg) was the daughter of Landgrave George III, Landgrave of Leuchtenberg and Margravine Barbara of Brandenburg- Ansbach.
Elisabeth of Oettingen
Elisabeth of Oettingen also known as" Elizabeth of Leuchtenberg"( born:; died: 9 July 1406) was a member of the House of Oettingen- Wallerstein by birth.
She was a Landgravine of Leuchtenberg by marriage and a lady in waiting for Elector Palatine and King of Germany Rupert.
Auguste, Duke of Leuchtenberg
Auguste Charles Eugène Napoléon, Duke of Leuchtenberg( 9 December 1810 – 28 March 1835) was the first prince consort of Maria II of Portugal.
Besides being the 2nd Duke of Leuchtenberg and 2nd Prince of Eichstätt, he also held the Brazilian noble title of Duke of Santa Cruz.
George Maximilianovich, 6th Duke of Leuchtenberg
Prince George Maximilianovich Romanowsky, 6th Duke of Leuchtenberg (29 February 1852 – 16 May 1912), also known as Prince Georgii Romanovsky or Georges de Beauharnais, was the youngest son of Maximilian de Beauharnais, 3rd Duke of Leuchtenberg and his wife, Grand Duchess Maria Nikolaevna of Russia.
Sergei Georgievich, 8th Duke of Leuchtenberg
Prince Sergei Georgievich Romanowsky, 8th Duke of Leuchtenberg (4 July 1890 – 7 January 1974) was the son of Prince George Maximilianovich Romanowsky, 6th Duke of Leuchtenberg and his second wife Princess Anastasia of Montenegro.
He succeeded his half-brother Alexander Georgievich as Duke of Leuchtenberg from 1942 until his death.
Alexander Georgievich, 7th Duke of Leuchtenberg
Alexander Georgievich, 7th Duke of Leuchtenberg, also known as Prince Alexander Georgievich Romanovsky or less commonly Alexander de Beauharnais (13 November 1881 – 26 September 1942) was the only son of George Maximilianovich, 6th Duke of Leuchtenberg by his first wife Duchess Therese of Oldenburg.
He was a descendant of Paul I of Russia from both of his parents.
Princess Anastasia of Montenegro
Princess Anastasia Petrović-Njegoš of Montenegro (4 January 1868 in Cetinje, Montenegro – 25 November 1935 in Cap d'Antibes, France) was the daughter of King Nikola
I Petrović-Njegoš of Montenegro (1841–1921) and his wife, Milena Vukotić (1847–1923).
Through her second marriage, she became Grand Duchess Anastasia Nicholaievna Romanova of Russia.
She and her sister "Militza" (Princess Milica), having married Russian royal brothers, were known colloquially as the "Montenegrin princesses" during the last days of Imperial Russia, and may have contributed to its downfall by the introduction of Grigori Rasputin to the Empress Alexandra.
Minamoto no Chikako
She was the mother of Prince Morinaga.
Charles Gordon-Lennox, 8th Duke of Richmond
Charles Henry Gordon- Lennox, 8th Duke of Richmond, 8th Duke of Lennox, 3rd Duke of Gordon,( 30 December 1870 – 7 May 1935), known as Lord Settrington 1870 – 1903, and as Earl of March 1903 – 1928, was a British Peer and politician.

Question: What is the place of birth of Sergei Georgievich, 8Th Duke Of Leuchtenberg's mother?
Answer: Cetinje