After being promoted to the rank of lieutenant general, and serving various governmental posts, he was then assigned as the Yerevan Forces commander of Russia's army during the Russo-Turkish War of 1877–1878.

Owing to his successes in battle, Arshak Ter-Gukasov was awarded medals by Imperial Russia and other foreign powers.

Arshak Ter-Gukasov was born in the Havlabar district of Tiflis, Georgia in 1819 to an Armenian family of clergymen originally from Shamkhor (today Şəmkir, Azerbaijan).

Due to his relative success in subsequent battles, notably in engagements with Chechen and Daghestani tribesmen in Dilim and Burtuna, he was promoted to the General of the Apsheron Infantry Regiment in 1859.

Additional factors included Russian hopes of recovering territorial losses suffered during the Crimean War, re-establishing itself in the Black Sea and supporting the political movement attempting to free Balkan nations from the Ottoman Empire.

The Russian force stood opposed an Ottoman Army of 100,000 men led by General Ahmed Muhtar Pasha.

The Caucasus Corps was led by a quartet of Armenian commanders: Generals Arshak Ter-Gukasov, Mikhail Loris-Melikov, Ivan Lazarev and Beybut Shelkovnikov.

[5] It was the forces under Ter-Gukasov, numbering at around 13,000 soldiers,[6] stationed near Yerevan, that commenced the first assault into Ottoman territory by capturing the town of Bayazid on 27 April 1877.

With a low loss of 100 men during the confrontation, historians William Allen and Paul Muratoff called Ter-Gukasov's engagement a "really brilliant operation".

He was buried in St. Kevork Armenian Cathedral next to Russian-Armenian military commanders he fought alongside during the Russian-Turkish war of 1877–78: Mikhail Loris-Melikov, Ivan Lazarev and Beybut Shelkovnikov.

[2] Arshak Ter-Gukasov is depicted during the siege of Bayazid in the first chapter of the novel Khent, written by Armenian writer Raffi.