[5] His first active service was in 1805, in the auxiliary army sent to the assistance of Austria against France, when he took part in the Battle of Austerlitz, 2 December 1805, where Austrian – Russian troops were defeated by the French under Napoleon.

[5] From 1807 to 1812, Ivan Paskevich was engaged in the campaigns against the Ottomans, and distinguished himself by many brilliant and daring exploits, being made a general officer in his thirtieth year.

[8] After the Persians unsuccessfully tried to recapture Echmiadzin and its surroundings, the tsar granted Paskevich the title of "Erivanskii"[9] (Count of Yerevan/Erevan), a million rubles and a diamond-mounted sword for his services.

At the same time he appointed the high-ranking Muslim cleric Mir-Fatah-Agha from Iran as head of the recently established Caucasus Committee.

Paskevich hoped that by the help of Mir-Fatah's high stature in the Muslim community, he could make a very valuable contribution to the Russian consolidation of power in the Caucasus.

In June 1831, after the death of Field Marshal von Diebitsch, commander of Russian troops in Congress Poland, Paskevich was appointed his successor in crushing the Polish uprising.

With Paskevich's participation, a decree was prepared in 1846, which prohibited the arbitrary removal by landlords of peasants, who had more than 3 morgen (1.7 hectares), from the land, the reduction or change of their plots, and abolished darmocha [pl] (duties in favour of landlords over and above barshchina [ru] and obrok ('levies') [ru]), forced hiring, tribute, and a number of other duties.

Though he laid siege to Silistria, Paskevich advocated aborting the campaign due to Austria's threat to intervene in the war.

On 9 June he suffered a combat injury and was compelled to return to Russia, handing command of the army to General Mikhail Dmitrievich Gorchakov.