[5] In the late 16th century several campaigns by the Terek Cossacks were carried out against the Ottoman Empire (Temryuk) which led the Sultan to complain to Ivan the Terrible.

During the Time of Troubles in 1606 four thousand Terek Cossacks left for the Volga to support their own candidate for the Tsar, Ileyka Muromets.

Also in 1720 the Rowers and Tereks were fully incorporated into the Russian Empire and during the Russo-Persian War (1722–1723), the Cossacks aided Peter I of Russia in his conquest of the eastern Dagestan and the capture of Derbent.

In 1735 by a new agreement with Persia the Sulak line was abandoned, and Agrakhan Cossacks were re-settled on the lower Terek Delta, and the fort of Kizlyar was founded.

When the Kalmyks arrived in the northwestern Caspian a combined campaign was waged against Temryuk during the Russo-Turkish War (1735–1739), where the Terek Cossacks were led by Atamans Auka and Petrov.

Major foreposts for Russian expansion into the central Caucasus were founded by the re-settlers including: Giorgiyevsk in 1777 by the Khopyor regiment, and Vladikavkaz in 1784.

After the joining of Georgia to Russia in 1801 and the subsequent Russo-Persian War (1804–1813), the Terek Cossacks spared some men and took part in combat under Yerevan, but on the whole most of them were in constant defence of their home lines.

In 1818 he changed the Russian tactics from defensive to offensive and began building the Sunzha-Vladikavkaz line where strongholds such as Groznaya and Vnezapnaya were founded.

From the 1870s onwards the Eastern Caucasus remained largely peaceful (if one discounts uprisings waged by the Chechens in the late 1870s and the occasional exchange of raids).

[7] In the 1880s the arrival of the railways and the discovery of oil made the Terek Oblast one of the wealthiest in the Caucasus, resulting in a large growth in Cossack and indigenous mountain populations.

Peace was preserved, by a complex Russian policy of supporting loyal clan leaders and free supplies of food and goods [8][unreliable source?]

Until 1914 the Terek Cossack Host wore a full dress uniform comprising a dark grey/black kaftan (knee length collarless coat) with light blue shoulder straps and braid on the wide cuffs.

Tall black fur hats were worn on all occasions with light blue cloth tops and (for officers) silver lace.

[12] The Terk and Kuban Cossacks of the Imperial Escort (Konvoi) wore a special gala uniform; including a scarlet kaftan edged with gold braid and a white waistcoat.

The unrequited mountainous peoples took full advantage of the crises, Chechens and Ingush on the Sunzha line wiping out several Cossack stanitsas.

Yet, according to Kenez, "The Chechen and the Ingush were never subdued and their raids and risings made the Northern Caucasus a festering sore for the Volunteer Army.

In the 1930s, to make the mountainous autonomies more sustainable in economical terms, they were united with the remaining Cossack holdings: the Sunzha district was retaken by the Chechen-Ingush ASSR, the former capital of the Terek Oblast, Vladikavkaz became the administrative centre for North Ossetia, likewise the Kabardino-Balkar Autonomous Oblast was also awarded to Cossack territories.

Thus by the start of the Second World War only the historical Terek Left-bank was not administered by autonomies, however, most of the administration and urban population of those regions was dominated by ethnic Russians.

This was paralleled with the gradual down-folding of anti-Cossack repressions and their eventual rehabilitation by the mid-1930s, including forming numerous units in the Red Army.

By November, the Battle of the Caucasus reached North Ossetia, and Germans were already making plans to lease the oilfields in Grozny.

During the 1920s and 30s, despite efforts of Soviet Union to pacify the mountainous peoples via different programmes, such as Korenizatsiya, there was still low-level criminal secession movements in the highlands.

Old problems of land ownership quickly resurfaced, and many returning Chechens and Ingush, forbidden to re-settle in the mountains, were settled in Cossack stanitsas.

Although this hid the historic adversity between Russians and Caucasus people, it never removed the tension, as both sides saw each other gaining favours at their expense.

However, in doing so, many wished to review the existing administrative borders in the Northern Caucasus, and return the Cossack regions, that belonged to the once Terek Oblast from the national autonomies.

Chechens feared that Cossacks were variously plotting to undermine the independence which they saw as a desperate necessity and to detach a large part of their state.

The chronic economic hardship of Chechnya during and after the Soviet period and the large income gap between Russians and Chechens before 1990 also worsened tensions.

[citation needed] President Dzhokhar Dudayev, himself married to a Russian, tried to suppress ethnic tensions, which he viewed as a destabilizing element to an already impoverished and internationally isolated republic.

However, the statements of the President about "hospitality" were not convincing enough, and Dudayev had other priorities, such as handling the economic conditions inherited from the Soviet age and international isolation, another major problem.

[citation needed] Many of the educated elite also lost their positions in government, industry and academia to locals connected with those in power (which previously they had a vast advantage in due to the situation after the return of the Chechens from exile).

[citation needed] After an attempted coup against Dudayev (who was seen as a threat to Russian oil transit) failed, Moscow responded with a military operation to reconquer Chechnya (see First Chechen War); many Terek Cossacks jumped at the opportunity to show their loyalty, and formed volunteer units that operated with the Russian Army.