Vannovsky, 1849 At the beginning of the Russo-Turkish War, he commanded the 12th Army Corps to crossed the
Danube, the Army Corps was later incorporated into the Ruschuk Detachment (the Eastern Detachment), for which he was appointed chief of staff of it, commanded by the
tsesarevich, the future emperor
Alexander III, whom he would become close friend with after the war. The Ruschuk Detachment was exceptionally powerful among other Russian units. It was composed of the
12th and the
13th Army Corps, 49
battalions, 19
Cossack divisions and 224 guns. The task of the detachment was to take the small
Ottoman towns of
Ruse and
Nikopol, but when they arrived, they were attacked by the
Ottomans and as a result, they went fully defensive, but they could still break through the Ottomans and won significant victories. Later on the Ottomans launched at
Katselovo, forcing the Russians to retreat to
Gorsko Ablanovo. There,
another battle would take place, which would once again end in an Ottoman victory. After some time, the Ottoman high command made a decision to attack the right flank and the center of the Ruschuk Detachment with 28
squadrons and 84 guns, in order to encircle the detachment from the rear. But the plan was later unravelled by Vannovsky, and the Russian Army soon went to defensive position. On 9 September, when the Ottomans attacked, they got counter-attacked by the Russians, inflicting considerable casualties on the Ottomans; nevertheless, the Ottomans had emerged victorious. Now with
Plevna captured, Commander-in-chief
Grand Duke Nicholas Nikolaevich changed the original plan completely, the Ruschuk Detachment went completely defensive, with the task of continue protecting the Russian rear.
Battle at Trastenik and Mechka On 14 November,
Suleiman Pasha with his men tried strike the Russian Army rear once again, and a decisive battle took place between the Bulgarian villages of
Trastenik and
Mechka. During the battle, the Ottomans, having superiority in manpower and artilleries, went on an offensive, inflicting the main blow at the right flank of the Russian Army. And the Russians, led by
Grand Duke Vladimir Alexandrovich, decided to retreat. Further unravelling revealed that the Ottomans planned to play defensive against the left and center of the Russians, and concentrate the troops to strike on the right flank of them. The battle developed well for the Russians, later with the support of the 2nd Brigade of the
35th Infantry Division, a Ukrainian Regiment and reinforced by the cavalry of , the Ruschuk Detachment advanced and launched an attack on the left flank of the Ottomans. The Ottomans' defense broke and the center and left flank of the Ruschuk Detachment went on an offensive, during which Ottoman troops completely broke down. In this battle, the Ruschuk Detachment's casualties were about 850 men, and the Ottomans lost more than 3,000 men. Later, for bravery and military distinction in the battle, the Tsesarevich was awarded the
Order of St. George of the 2nd degree, the highest military decoration in the Russian Empire. While General Vannovsky was appointed
General Adjutant and awarded the order of the 3rd degree with the inscription "As a reward of courage, bravery and orderliness rendered in affairs against the Turks and active participation in the repulse of repeated enemy attacks on the positions occupied by the troops of the 12th and 13th Army Corps". After that victory, the Ruschuk Detachment continued carrying out defensive tasks. The Ruschuk Detachment by that time was considered to be the road to victory by many Russian officers through all the minor but extremely important tasks successfully carried out by the detachment. By the end of the year, the Russian high command described the actions of the Ruschuk Detachment over the war as follows: Later, the Ruschuk Detachment was tasked with interrupting the Ottoman communication line between Ruse and
Shumen, in order to capture
Silistra. In January, they fulfilled the order, interrupting the Ottoman communication between Ruse and Shumen, and captured Silistra. After the battle, Grand Duke Nicholas Nikolaevich offered the Tsesarevich to go on a vacation, he refused and was accepted by the Grand Duke, this would eventually contribute to the development of the successful career of Vannovsky: Vannovsky's detachment was the first in Russian military history to receive biscuits as food, rather than having bread, to reduce the possibility of getting
gastrointestinal disease. This practice then proceeded to extend throughout the Russian Army. During the war, General Vannovsky showed his talent as a chief of staff, and after the war, he was appointed
adjutant-general and commander of the Eastern (later renamed Northern) Detachment. After he was appointed to the detachment, he used this chance to organize the troops as an independent commander, which would soon prove very useful after he became the Minister of War. After a year or so, he was again appointed commander of the 12th Army Corps, the corps that he commanded prior to the war. In 1881, Alexander III ascended to the throne, and many liberal government officials of
Alexander II were removed from office, including Minister of War
Count Milyutin. After Milyutin's dismissal, Vannovsky was appointed manager of the
Ministry of War. ==Minister of War==