The marriage, arranged by the Russian Imperial family in an attempt to control the Grand Duke's excesses, was unhappy.

Deeply religious and very involved in charity work, Alexandra founded a training institute for nurses in St Petersburg in 1865.

A carriage accident left her almost completely paralyzed and, in November 1880, Alexandra went abroad to improve her health, compelled by her brother-in-law Tsar Alexander II.

She recovered her mobility and, in 1889, she founded the Pokrovsky Nunnery, Kiev, a convent of nursing nuns with its own hospital, to provide free treatment for the poor.

[1] She was the eldest of the eight children of Duke Peter of Oldenburg and his wife Princess Therese of Nassau-Weilburg, half-sister of Sofia of Nassau, queen consort of Oscar II of Sweden.

[1] Alexandra belonged to the House of Holstein-Gottorp but grew up in Russia,[2] where her family was closely related to the Romanov dynasty.

Duke Peter, Alexandra's father, was the only surviving son of Grand Duchess Catherine Pavlovna, the fourth daughter of Tsar Paul I of Russia.

[3] Alexandra's mother, Princess Therese of Nassau-Weilburg, was interested in painting and like her husband was deeply involved in charity work, so much so that she was considered an eccentric.

[4] Seven years Alexandra's senior, Grand Duke Nicholas was a military officer who had numerous love affairs.

[6] The Russian Imperial family, in an attempt to control the Grand Duke's excesses, had propelled Nicholas to marry Alexandra, hoping that she would have a good influence on him.

[8] There, in their apartments on the ground floor, nine months after their wedding, Alexandra gave birth to their first child on 18 November 1856, Grand Duke Nicholas Nikolaevich of Russia the Younger.

[8] In 1863, a church was added to her palace under the care of Alexandra's confessor, Archpriest Vasili Lebedev, who had great influence over the deeply devoted grand duchess.

[8] Lacking in beauty and social graces, Alexandra avoided court functions, instead of dividing her time between her charitable activities and farm work on the family's summer residence, Znamenka Palace, near Peterhof, which had been given to them as a wedding present.

The following year, Alexandra became chairwoman of the board of trustees of the office of Empress Maria Alexandrovna which oversaw orphanages, founding homes, schools and hospitals.

[12] In spite of the differences in character and outlook, Alexandra and her husband lived in harmony for the first ten years of their married life.

[12] Initially, Grand Duke Nicholas respected and admired his wife's interest in charities and medicine as well as her being extremely religious.

He financed a hospital in the city where her theories could be developed and put into practice and poor patients received care without charge.

[2] As time went by, Grand Duke Nicholas Nicholaievich grew tired of Alexandra's increasing preoccupation with religion and began complaining of his wife's lack of glamour and distaste for society.

[12] In 1865, the grand duke started a permanent relationship with Catherine Chislova, a dancer from the Krasnoye Selo Theater.

[10] According to some sources, Alexandra Petrovna retaliated against her husband's infidelity by taking a lover and, in 1868, gave birth to an illegitimate son.

[10] When the Grand Duke arranged a change of class into the gentry for his mistress and the couple's illegitimate children, Alexandra Petrovna appealed to Alexander II to intervene, but she found her brother-in-law less than sympathetic.

During the Russian-Turkish War, 1877–1878, Grand Duke Nicholas Nikolaievich commanded the Russian army of the Danube while Alexandra organized a sanitary unit at her own expense.

Appalled by the scandal, Alexander II was not sympathetic towards Alexandra and instead made her leave Russia indefinitely to seek medical treatment abroad.

[16] In November 1880, the Grand Duchess left for Italy with her two sons on board the naval steamer Eriklik [ru].

Alexandra vehemently refused to grant a divorce and Nicholas hoped that he could be a widower so he could remarry, as it had been the case of his brother Alexander II, who after his wife's death married his mistress.

[19] There, with the permission of Metropolitan Platon of Kiev [ru] and investing her own money, she founded the Pokrovsky Nunnery, a convent of nursing nuns with its own hospitals, asylums and dispensary to provide free treatment for the poor.

For the rest of her life, she worked at the hospital performing nursing duties, helping contagious patents and cleaning infected wounds.

In May 1892, she underwent a successful breast cancer operation and spent some time in Corfu while she recuperated, returning to work in February 1893.

On the day of her burial, Emperor Nicholas II and Empress Alexandra Feodorovna attended a memorial service held in the Moscow Kremlin palace church.