Konstantin Petrovich Oldenburgskiy; 9 May 1850 – 18 March 1906) was the youngest son of Duke Peter Georgievich of Oldenburg and his wife, Princess Therese of Nassau-Weilburg.

[1] Known in the court of Emperor Nicholas II as Prince Constantine Petrovich Oldenburgsky, he was the father of the Russian Counts and Countesses von Zarnekau.

During the 18th Century, the Dukes of Holstein-Gottorp gained influence through a carefully planned series of marital alliances with the royal houses of Germany, Denmark, Sweden, Norway and Prussia.

Constantine's father, Duke Peter Georgievich, had won respect serving as a colonel in the Emperor's Semenovsky Life Guards Regiment in the 1820s, had become a Russian senator in 1834, had founded the Imperial School of Jurisprudence in 1835, and had played a leading role in funding education and hospitals throughout Russia.

Duke Constantine Petrovich was registered from birth until 1869 as an ensign in his father's honor unit, the Semenovsky Regiment of the Life Guard Infantry.

At the end of the war, between 1881 and 1887, Constantine Petrovich commanded the 1st Cavalry Regiment of the Hopersky Kuban Cossacks, stationed near Kutaisi, a town in the Georgian province of Imeretia, just north of the battlefield at Kars.

At this time, the Black Sea coast in Georgia became the "Riviera of Russia," a popular place for wealthy Russians to visit on vacation, and the arts scene in Tiflis began to thrive.

She was starring in the lead role of the play "The Knight in the Panther's Skin," a production mounted by Princess Cholokashvili in order to raise funds for a monument to one of Georgia's greatest poets, Shota Rustaveli.

The scenes and backdrops for the show were painted by the famous Hungarian court painter Mihály Zichy, and the play was a tremendous success, winning "endless applause."

After the show, Constantine Petrovich began a reckless flirtation with Agrippina and his attentions to the wife of a fellow officer caused people to gossip.

On 20 October 1882, Constantine entered into a morganatic marriage with a Georgian noblewoman Agrippina Japaridze, divorced Princess Dadiani, described by one source as wealthy and an "exceedingly lovely girl".

[6] Grand Duke Peter II, head of the House of Oldenburg, created her Countess von Zarnekau on the day of their wedding, with the same title passing to their children.

Constantine Petrovich bought stock in local mines and oil wells, and began selling fruit, melons, vegetables and other farm goods abroad.

In his capacity as a cavalry general, Constantine Petrovich oversaw the local stables, gradually becoming an expert horse-trader, providing services to Russian officers and aristocrats in the region.

The record indicates Constantine Petrovich became a member of the Veterinary Council of the Russian Empire, and he eventually became the "director general of all the Imperial horse-breeding establishments.

Duke Constantine also made regular visits to Alexandrovsk (Zaporozhe), home of the Zaparozhian cossacks, in order to buy and sell horses.

The Memoirs of Count Witte indicate that Duke Constantine and his family spent their vacations visiting with his sister, the Grand Duchess Alexandra Petrovna, at her summer palace in Kiev.

His eldest son, Count Nicholas von Zarnekau, a Cornette in His Supreme Majesty's Garde a Cheval (Horse Guards),[8] lived at 4 Konnogvardeisky Boulevard.

Designed in the "Brick Gothic" style, the Duke of Oldenburg's Palace served as the family's main residence in the Caucasus for the next ten years.

Constantine Petrovich's family attracted controversy in the year 1900, when he celebrated the wedding of his 17-year-old daughter, Countess Alexandra von Zarnekau, to the Emperor's half-uncle, Prince George Alexandrovich Yuryevsky at Nice, France.

[12] After the death of Empress Maria Alexandrovna in June 1880, Emperor Alexander II married Catherine Dolgorukov, and made her three children legitimate.

Foreseeing this hostility, Emperor Alexander II had settled a large fortune on Princess Yurievsky—3.5 million rubles parked in Swiss bank accounts.

[13] When she had arrived in France, she was reported to be very wealthy and found herself immediately surrounded by a circle of sympathetic Russian émigrés who hoped to receive her financial aid.

[14] However, the rumor gained traction when a young Georgian nationalist, Prince Viktor Nakachidze, was convicted in late 1885 for participating in a nihilist bomb plot to kill the Emperor.

[16] In 1890, Rachkovsky managed to entrap and convict Prince Victor Nakachidze and 26 of his associates as they prepared to set off bombs at the 1890 "Exposition Universelle" (World Fair) in Paris.

In 1896, Prince Viktor Nakachidze resurfaced in Italy, where he gave up making bombs and masterminded an attempt to kill Emperor Nicholas II with poison.

Nakachidze was arrested in Nice by French police "who affirm that they have full proof that the Prince was engaged in a plot to assassinate the Russian Emperor should he visit the Riviera.

Emperor Nicholas II therefore had reason to look with suspicion on the marriage arranged in 1900 between the eldest daughter of Duke Constantine Petrovich and Prince George Yurievsky.