Grand Duke Nicholas Nikolaevich of Russia (Russian: Великий князь Николай Николаевич) (8 August 1831 in Tsarskoye Selo – 25 April 1891 in Alupka) was the third son and sixth child of Tsar Nicholas I of Russia and Alexandra Feodorovna. He may also be referred to as Nicholas Nicolaievich the Elder to tell him apart from his son. Trained for the military, as a Field Marshal he commanded the Russian army of the Danube in the Russo-Turkish War, 1877–1878.

Grand Duke Nicholas Nikolaevich was born on 8 August 1831 at Tsarskoye Selo in St. Petersburg.

His father arranged for Nicholas Nikolaevich a career in the army. On the day he was born, he was appointed honorary colonel in the Life Guard Lancers and enlisted into the Life Guard Sappers battalion. A soldier most of his life, he first saw active service in the Crimea War, when he was in his early twenties, taking part in the battle of Inkerman (1854). Grand Duke Nicholas Nicolaievich showed a special interest in military engineering. In 1856, he was appointed as general Inspector of engineers and in 1864, he became commander of the Imperial Guard. In 1873, he accompanied his brother, Alexander II, to Berlin at the meeting of the three emperors: Russia, Germany and Austria.

The epitome of his career was the Russo-Turkish War, 1877–1878, when Nicholas Nicolaievich was appointed Commander-in- Chief of the Russian armies of the Danube, although his reputation as a strategist was very low. The Grand Duke had no particular distinction in early successes in the conflict and these were followed by terrible reverses of the armies under his orders. After the expulsion of the Russian troops from Rumelia and unsuccessful attacks at Plevna, Nicholas Nicolaievich was removed from actual command, although in theory he remained in his post. The victory of his subordinates allowed him to participate in the success at Adrianople and the Treaty of San Stefano, but after the war ended, he was criticized for not seizing Constantinople when his headquarters were already established in Adrianople. The Grand Duke also suffered the acute embarrassment of being charged with financial irregularities, of receiving bribes and embezzling money from the government.

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