The March Days or March Events (Azerbaijani: Mart hadisələri) was a period of inter-ethnic strife and clashes which took place between 30 March – 2 April 1918 in the city of Baku and adjacent areas of the Baku Governorate of the Transcaucasian Commissariat.

Facilitated by a political power struggle between Bolsheviks with the support of the Armenian Revolutionary Federation (Dashnaktsutiun) on one side and the Azerbaijani Musavat Party on another, the events led to rumours of a possible Muslim revolt on the part of Bolshevik and Dashnak forces and the establishment of the short-lived Baku Commune in April 1918.

Most historic sources and accounts interpret the March events in the context of civil war unrest, while contemporary Azerbaijani sources officially refers to the March Days as a genocide. These were followed by the September days where 10,000 ethnic Armenians were massacred by Army of Islam and their local Azerbaijani allies upon capturing Baku.

Following the February Revolution, a Special Transcaucasian Committee, including Armenian, Azerbaijani and Georgian representatives, was established to administer parts of the South Caucasus under the control of the Russian Provisional Government. After the October Revolution, on 11 November 1917, this committee was replaced by the Transcaucasian Commissariat, also known as the Sejm, with headquarters in Tbilisi. The Sejm opposed Bolshevism and sought separation of the South Caucasus from Bolshevik Russia. To prevent that, on 13 November 1917, a group of Bolsheviks and Left Socialist-Revolutionaries (SR) proclaimed the Baku Soviet, a governing body which assumed power over the territory of Baku Governorate under the leadership of Bolshevik Stepan Shahumyan. Although the Baku Soviet included Azerbaijanis and Armenians who were neither Bolsheviks nor necessarily sympathetic towards Bolshevik ideas, the two nationalist parties and members of the Sejm ― the Musavat and Armenian Revolutionary Federation ― refused to recognize its authority. The Baku-based Musavat dominated the Muslim National Councils (MNCs), a representative body which eventually formed the first Parliament of the Azerbaijan Democratic Republic (ADR). Mammad Hasan Hajinski chaired the Temporary Executive Committee for the MNCs, while Mammed Amin Rasulzade, Alimardan Topchubashev, Fatali Khan Khoyski and other prominent political figures were among the 44 Azerbaijani delegates to the Sejm. Meanwhile, the ARF, which was established in Tbilisi, formed a 27-member Armenian delegation to the Sejm. The leader of the Baku Soviet, Shahumyan, kept contacts with ARF and viewed it as a source of support for eliminating Musavat influence in Baku.

After the October Revolution, the Russian army fell apart and its units fled the front lines en masse, often harassing local residents. Concerned with the situation, the Sejm established a Military Council of Nationalities, with Armenian, Azerbaijani and Georgian representatives, which had troops at its disposal. When a large group of Russian soldiers withdrew from the Ottoman front line in January 1918, the head of the council, Georgian Menshevik Noe Ramishvili, ordered their disarmament. The Russian soldiers were stopped near Shamkhor station and, upon a refusal to surrender, were attacked by Azerbaijani bands in what became known as the Shamkhor massacre. The Baku Soviet played out this incident into its favor against the Sejm.

On 10–24 February 1918, the Sejm adopted a declaration of independence. In the meantime, to support Armenian resistance against the Ottoman Empire, the British government attempted to re-organize and train a group of Armenians from the Caucasus under the leadership of General Lionel Dunsterville in Baghdad. The Allies had also provided Armenians with 6,500,000 rubles ($3,250,000 of 1918 value) in financial assistance. In addition, the Armenian National Organization of the Caucasus formed an Armenian Military Committee in Petrograd under General Bagradouni and called upon all Armenian military personnel scattered throughout Russia to mobilize on the Caucasus front. In response to this call, by early March 1918, a large number of Armenians had gathered in Baku, joining a group of 200 trained officers accompanied by General Bagradouni and the ARF co-founder Stepan Zorian (Mr. Rostom).

The Azerbaijanis grew increasingly suspicious that Shahumyan, who was an ethnic Armenian, was conspiring with the Dashnaks against them. The units of the Caucasian Native Cavalry Division, composed of Caucasian Muslims who had served in the Imperial Russian Army, thus nicknamed the "Savage" Division, disarmed a pro-Bolshevik garrison in Lankaran, and Dagestani insurgents under imam Najmuddin of Gotzo drove the Bolsheviks out of Petrovsk, severing Baku's land communications with Bolshevik Russia. The Armistice of Erzincan, followed by the Treaty of Brest-Litovsk signed on 3 March 1918, formalized Russia's exit from World War I. According to Richard G. Hovannisian, a secret annex to the Treaty of Brest-Litovsk obligated the Bolsheviks to demobilize and dissolve ethnic Armenian bands on territories previously under Russian control. At the subsequent Trabzon Peace Conference, the Ottoman delegation called for a unified position of the Sejm before the negotiations could be completed. The Bolsheviks grew increasingly concerned about the emerging Transcaucasian Federation, and in the given situation, had to choose between Musavat and ARF in the struggle to dominate Transcaucasia's largest city. Thus the Baku Soviet was drawn into the nationalistic struggle between the Azerbaijanis and the Armenians, trying to utilize one people against the other.

As Baku produced 7 million tons of oil per year (about 15% of global oil production), during World War I the city remained in the sights of the major warring powers. Even though most of the oil fields were owned by Azerbaijanis and less than 5 per cent by Armenians, most of the production/distribution rights in Baku were owned by foreign investors, primarily the British. At the beginning of 1918, Germany transferred General Friedrich Freiherr Kress von Kressenstein from the Sinai and Palestine Campaign to establish the German Caucasus Expedition with the aim of capturing Baku. In response, in February 1918, the British dispatched General Lionel Dunsterville with troops to Baku through Enzeli, in order to block the German move and to protect the British investments.