Eberhardt was born in
Patras, Greece, where his father, August Eberhardt, served as the consul for the Russian Empire. He had
Westphalian ancestry; his grandfather Johann Karl Eberhardt moved from
Hamburg to
Russia during the early-19th century. He was not baptised a
Lutheran but an
Orthodox because his mother was Russian. Eberhardt graduated from the
Russian Marine Cadet Corps in 1878. From 1882 to 1884 he served in the
Siberian Military Flotilla as a signals officer. In 1886, he became a flag officer and adjutant to Admiral
Ivan Shestakov (
Minister of the Navy, in office: 1882-1888) and in 1891 he became a flag officer to Admiral commanding the
Russian Pacific Squadron. In 1896 Eberhardt transferred to the
Black Sea Fleet, serving as gunnery officer on the battleships
Ekaterina II and
Chesma. In 1898 he moved back to the
Russian Far East; he commanded the
cruiser Admiral Nakhimov and took part in suppressing the
Boxer Rebellion of 1899-1901 in China. During the
Russo–Japanese War of 1904-1905 Eberhardt served as chief naval aide to
Yevgeni Ivanovich Alekseyev, the (in office: 1903-1904). In 1905 he captained the battleship
Imperator Aleksandr II and in 1906 became captain of the battleship
Panteleimon. He was promoted to rear admiral in 1907 and to vice admiral in 1909. Eberhardt served as Chief of the
Russian Naval General Staff from 1908 and as Commander-in-Chief of the Black Sea Fleet from 1911. Following the outbreak of World War I in 1914, his top achievement was setting up a naval blockade of the
Zonguldak coal fields from 1915 and thus choking the coal supply of the German-
Turkish fleet. He also commanded the Russian battleship squadron during the
Battle of Cape Sarych (near the Crimea) in November 1914. However, he showed reluctance to start further offensive actions against Ottoman positions in the
Bosporus, and
Aleksandr Kolchak succeeded him in June 1916. Eberhardt retired from service in December 1917. The
Cheka arrested him in 1918, but then released him. He died in 1919 and was buried in the
Novodevichy Cemetery () in
Petrograd. ==Honours and awards==