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Chronology of the occupation of Azerbaijani lands by Armenia
14 May 1805 – Treaty of Kurakchay between the Russian Empire and the Karabakh khanate, signed by Ibrahim Khalil Khan of Karabakh.
10 February 1828 – Treaty of Turkmenchay between the Russian and Persian Empires, ceding lands north of the Araz river to Russia. The government of Iran was obliged not to prevent Armenians from moving to the Armenian region created in the territory of these khanates, which contributed to the unification of the Armenian people within the Russian Empire.
Following the signing of the Gulustan and Turkmenchay treaties, there was a very rapid mass resettlement of Armenians to Azerbaijani lands and an artificial territorial division subsequently emerged. In 1830 population of Yerevan was Armenians 3,937 (34.3%); Muslims 7,331 (63.9%)
April 1919 – the Allied Powers recognized the provisional Governor-Generalship of Karabakh, which was established by the Azerbaijan Democratic Republic to be under Azerbaijani jurisdiction. In 1919, the Armenian National Assembly of Nagorno-Karabakh officially recognized Azerbaijan’s authority.
5 July 1921 – the Caucasian Bureau decided to retain Nagorno-Karabakh within the Azerbaijan SSR, not to “transfer” or “subject” it to Azerbaijani rule, as the Armenian side claims:
“Taking into account the necessity of national peace between the Muslims and the Armenians, the economic relations between upper and lower Karabakh and the permanent relations of upper Karabakh with Azerbaijan, Nagorno-Karabakh shall be retained within the Azerbaijan SSR and broad autonomy shall be given to Nagorno-Karabakh with Shusha city as an administrative centre”.
7 July 1923 – the Azerbaijan Central Executive Committee established by decree the Nagorno-Karabakh Autonomous Region (Nagorno-Karabakh Autonomous Oblast – NKAO), of 4,400 km2. In doing so, they specifically selected villages with Armenian-majority populations for inclusion.
23 December 1947 and 10 March 1948 – On the pretext of resettling the Armenians arriving from abroad, the Council of Ministers of the USSR took special decisions on the resettlement of the Azerbaijani population from the Armenian SSR to the Kur-Araz lowlands in the Azerbaijan SSR. As a result, between 1948 and 1953 more than 150,000 Azerbaijanis were forcibly resettled from their historical homelands — the mountainous regions of Armenia — to the then waterless steppes of Mughan and the Mil plateau. By mid 1961, 200,000 Armenians had immigrated to Armenia and between 1962 and 1973, 26,100 more arrived.
End of 1987 – Armenia started making overt territorial claims on Nagorno-Karabakh and attacks on Azerbaijanis, both in the autonomous oblast and Armenia itself with expulsions of Azerbaijanis from the Armenian SSR and Nagorno-Karabakh. 
20 February 1988 – Agitations led to Armenians in the Nagorno-Karabakh Autonomous Republic of the Azerbaijan SSR requesting transfer to the Armenia SSR.
On 22 February 1988 – near the settlement of Asgaran on the Khankendi- Aghdam highway, Armenians opened fire on a peaceful demonstration by Azerbaijanis protesting against that decision by the Soviet of People’s Deputies of the NKAO, killing two Azerbaijani youths, who became the first victims of the conflict.
26-28 February 1988 – 26 Armenians and Azerbaijanis were killed as a result of disturbances in Sumgait. It is notable that one of the leading figures in these events was a certain Edward Grigorian, an Armenian native of Sumgait, who was directly involved in the killings and violence against the Armenians and pogroms in the Armenian neighbourhoods. In fact, the events in Sumgait, used by the Armenian leadership to launch an extensive anti-Azerbaijani campaign and justify ensuing anti-Azerbaijan aggression, had been planned and prepared in advance. The events in Sumgait could hardly have been carried out without powerful outside support. As The Times wrote, the KGB leadership tried “to weaken the Kremlin’s authority and powerbase” and “organised acts of provocation, using genuine local dissatisfaction as a base, in cities across the Soviet Union, including Sumgait and Baku…”.
12 June 1988 – at a meeting of the Nagorno-Karabakh regional soviet in the absence of the Azerbaijani deputies, an unlawful decision was adopted on the withdrawal of the NKAO from the Azerbaijan SSR.
15 June 1988 – the decision adopted by the NK region soviet on the withdrawal of the NKAO from the Azerbaijan SSR was accepted by the Armenian SSR.
17 June 1988 – the decision adopted by the NK region soviet on the withdrawal of the NKAO from the Azerbaijan SSR was rejected by the Azerbaijan SSR.
18 July 1988 – the Presidium of the Supreme Soviet of the USSR, the body with primary authority, formally decided to leave the NKAO within the Azerbaijan SSR. In other words, it confirmed that Nagorno-Karabakh formed part of the Azerbaijan SSR.
1 December 1989 – The Supreme Soviet of the Armenian SSR adopted a resolution on the “reunification of the Armenian SSR and Nagorno-Karabakh”.
10 January 1990 – the Presidium of the Supreme Soviet of the USSR adopted a resolution on the “Nonconformity With the USSR Constitution of the Acts on Nagorno-Karabakh Adopted by the Armenian SSR Supreme Soviet on 1 December 1989 and 9 January 1990”, declaring illegal the claimed unification of the Armenian SSR with Nagorno-Karabakh without the consent of the Azerbaijan SSR.
2 September 1991 – the Armenians of Nagorno-Karabakh adopted a “Declaration of Independence of the Nagorno-Karabakh Republic” (“NKR”).
27 November 1991 – a “Declaration of Independence of the Nagorno-Karabakh Republic” was declared invalid by the Azerbaijan SSR and by the USSR State Council and the following day by the USSR Committee for Constitutional Oversight.
10 December 1991 – A “referendum on independence” was held in Nagorno-Karabakh on (without the support or consent of Azerbaijan of which it legally constituted a part), which was confirmed two days later by an “Act on the Results of the Referendum on the Independence of the Nagorno-Karabakh Republic”.
25-26 February 1992 – Khojaly massacre. 613 Azerbaijanis killed, including 63 children, 106 women and 70 elders, 8 families were completely exterminated. 1,275 were taken hostage. The fate of 150 people remains unknown.
8 May 1992 – Shusha, the Azerbaijani-populated administrative centre of the district within NK was occupied.
18 May 1992 – Lachin district occupied (first district outside Nagorno-Karabakh). Six other districts subsequently occupied and emptied of their overwhelmingly Azerbaijani populations.
June 1992 – the so-called Minsk Group was established under the auspices of Organisation for Security and Co-operation in Europe (OSCE, formerly Commission on Security and Cooperation in Europe) tasked to bring peaceful resolution for the Armenian-Azerbaijan Nagorno-Karabakh conflict, which failed to reach any lasting peaceful resolution as yet. Three Minsk Group co-chair countries are Russia, France and the United States of America.
6 April 1993 – Kalbajar district, adjacent to NK was occupied.
30 April 1993 – UN Security Council resolution No. 822. Demanded “immediate withdrawal of all occupying forces from the Kelbadjar district and other recently occupied areas of Azerbaijan.” 
23 July 1993 – Aghdam district, adjacent to NK was occupied.
29 July 1993 –UN Security Council resolution No. 853. Condemned the seizure of Aghdam and demanded the “immediate, complete and unconditional withdrawal of the occupying forces involved from the district of Agdam and all other recently occupied areas of the Azerbaijani Republic.” 
23 August 1993 – Jabrayil and Fuzuli districts, adjacent to NK was occupied.
31 August 1993 – Gubadly district, adjacent to NK was occupied.
14 October 1993 – UN Security Council resolution No. 874. Reaffirmed “the inviolability of international borders and the inadmissibility of the use of force for the acquisition of territory.”
29 October 1993 – Zangilan district, adjacent to NK was occupied.
12 November 1993 – UN Security Council resolution No. 884. Demanded “the unilateral withdrawal of occupying forces from the Zangelan district and the city of Goradiz and…. from other recently occupied areas of the Azerbaijani Republic.”
12 May 1994 – With the Bishkek Protocol, a ceasefire came into effect. 
25 January 2005 – Parliamentary Assembly of the Council of Europe resolution No. 1416 regretted that, “Considerable parts of the territory of Azerbaijan are still occupied by Armenian forces.” And reiterated “that the occupation of foreign territory by a member state constitutes a grave violation of that state’s obligations as a member of the Council of Europe and reaffirms the right of displaced persons from the area of conflict to return to their homes safely and with dignity.” 
14 March 2008 – United Nations General Assembly resolution 62/243 “Reaffirms continued respect and support for the sovereignty and territorial integrity of the Republic of Azerbaijan within its internationally recognized borders”.
20 May 2010 – European Parliament resolution, The Need for an EU Strategy for the South Caucasus (2009/2216(INI)). Demanded “the withdrawal of Armenian forces from all occupied territories of Azerbaijan.” 
Refugees and Internally Displaced Persons (IDPs) – As a result of ethnic cleaning by Armenia nearly one million Azerbaijanis were expelled from the occupied territories of NK, seven adjacent districts as well as Armenia. In its resolution of 20 December 1993, the General Assembly of the United Nations noted with alarm “that the number of refugees and displaced persons in Azerbaijan has recently exceeded one million”. The UN High Commission for Refugees has stated that “Azerbaijan hosts one of the largest IDP populations per capita in the world”.
Last escalation at the contactn line (April, 2016) – Typically Armenian attacks against Azerbaijani soldiers and civilians have intensified at times when peace negotiations are being mediated by international organizations. This appears to be an establised technique by which to maintain the status quo and entrench its positions in the occupied lands.
The most recent violation of the ceasefire began in the early morning of 2 April 2016 when Armenia’s military attacked Azerbaijani soldiers and civilians from their positions in the occupied territories. The assault was launched along the Line of Contact, striking adjacent populated areas and included intensive fire involving heavy artillery and large-calibre weapons. 34 towns and villages along the Line of Contact came under attack resulting in casualties among Azerbaijani civilians, including children. There was also substantial damage to public and private property. President Sargsyan made it clear that peace was not on his agenda by saying:“War can break out at any moment”.
 See, e.g., I. Shopen, Historical monument of the status of the Armenian oblast in the period of its annexation to the Russian Empire (Saint-Petersburg: Publishing House of the Emperor’s Academy of Sciences, 1852), pp. 636, 639-641, 706; N. Shavrov, A new challenge to the Russian issue in Transcaucasia: Upcoming sale of Mughan to foreigners (Saint-Petersburg: Publishing House of the Editorial Board of the Ministry of Finance Periodicals, 1911), pp. 59-60.
 Provisional agreement between the Government of Azerbaijan and the Armenians of Nagorno-Karabakh, 26 August 1919 года. For text, see To the History of Formation of the Nagorno-Karabakh Autonomous Oblast of the Azerbaijan SSR. 1918-1925: Documents and Materials (Baku: Azerneshr, 1989), pp. 23-25. See also Tadeusz Swietochowski, Russia and Azerbaijan: A Borderland in Transition (New York: Columbia University Press, 1995), pp. 75-76.
 A/63/781-S/2009/156, pp. 8-9, paras. 30 and 34.
 Extract from the Protocol of the plenary session of the Caucasian Bureau of the Central Committee of the Russian Communist (Bolsheviks) Party of 5 July 1921. For text, see To the History of Formation of the Nagorno-Karabakh Autonomous Oblast of the Azerbaijan SSR. 1918-1925: Documents and Materials, p. 92.
To the History of Formation of the Nagorno-Karabakh Autonomous Oblast of the Azerbaijan SSR. 1918-1925: Documents and Materials, pp. 152-153.
 Documents of Foreign Policy of the USSR (Moscow: State Publishing House of Political Literature, 1962), volume 6, note 33, p. 611.
 History of the Armenian people, p. 418.
 According to Thomas de Waal, as early as in February 1986 one activist of the separatist movement, Muradian, travelled to Moscow from Yerevan “with a draft letter that he persuaded nine respected Soviet Armenian Communist Party members and scientists to sign” with the purpose of separation of Nagorno-Karabakh from Azerbaijan and its annexation to Armenia, op. cit., pp. 17-20.
 Vladimir Kryuchkov. Hardline Soviet Communist who became head of the KGB and led a failed plot to overthrow Mikhail Gorbachev, Times Online, 30 November 2007, http://www.timesonline.co.uk/tol/comment/obituaries/article2970324.ece.
 Decision of the eighth meeting of the twentieth convocation of the Soviet of People’s Deputies of the Nagorno-Karabakh Autonomous Region proclaiming the withdrawal of the Nagorno-Karabakh Autonomous Region from the Azerbaijani SSR, 12 July 1988; see Vaan Arutunyan, pp. 113-115.
 Resolution of the Supreme Soviet of the Armenian SSR on the reunification of the Armenian SSR and Nagorno-Karabakh, 1 December 1989. Kommunist newspaper, 2 December 1989.
 United Nations General Assembly resolution 48/114, entitled “Emergency international assistance to refugees and displaced persons in Azerbaijan”.