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.
Princess Maria Maximilianovna of Leuchtenberg
Princess Maria Maximilianovna of Leuchtenberg, also known as Princess Maria Romanovskya, Maria, Princess Romanovskaja, Maria Herzogin von Leuchtenberg or Marie Maximiliane (16 October 1841 – 16 February 1914) was the eldest daughter of Maximilian de Beauharnais, 3rd Duke of Leuchtenberg and his wife Grand Duchess Maria Nikolaevna of Russia.
She married Prince Wilhelm of Baden.
The couple's son, Prince "Maximilian" of Baden, was Germany's last Imperial chancellor.
Princess Maria Pia of Bourbon-Parma
Princess Maria Pia of Bourbon- Parma( née Princess Maria Pia of Savoy; born 24 September 1934) is the eldest daughter of Umberto II of Italy and Marie- José of Belgium.
She is the older sister of Princess Maria Gabriella of Savoy, Vittorio Emanuele, Prince of Naples, and Princess Maria Beatrice of Savoy.
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.
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.
Grand Duchess Maria Nikolaevna of Russia (1819–1876)
Grand Duchess Maria Nikolaievna of Russia
(18 August 1819 – 21 February 1876) was a daughter of Emperor Nicholas I of Russia, and sister of Alexander II.
In 1839 she married Maximilian, Duke of Leuchtenberg.
She was an art collector and President of the Imperial Academy of Arts in Saint Petersburg.
Princess Eugenia Maximilianovna of Leuchtenberg
Princess Eugenia Maximilianovna of Leuchtenberg( 1 April 1845 – 4 May 1925) was a daughter of Maximilian de Beauharnais, 3rd Duke of Leuchtenberg and his wife Grand Duchess Maria Nikolaevna of Russia.
Although she was a member of the French House of Beauharnais, she was born and raised in her mother's native country, Russia.
In 1868, she married her distant cousin, Duke Alexander Petrovich of Oldenburg.
The couple had an only child, Duke Peter Alexandrovich of Oldenburg.
Princess Eugenia and her husband were particularly noted for their extensive philanthropy throughout Russia; so much so in fact that by 1914, a newspaper source could claim that" there[ were] probably not two who are so universally beloved as the Duke and Duchess of Oldenburg".
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.
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.

Question: Where did Princess Maria Maximilianovna Of Leuchtenberg's mother die?
Answer: Saint Petersburg