Analysis of information sources in references of the Wikipedia article "March Days" in English language version.
The contents of the ultimatum presented by the Bolsheviks and accepted by the Musavat:
We demand the immediate end of the military activity opened against Soviet power in the city of Baku; we demand the immediate surrender of fortified posts and the destruction of trenches. In order to avoid repetition in the future of such acts, the Committee of Revolutionary Defense demands:
1. Open and unconditional recognition of the power of the Baku Soviet of Workers, Soldiers, and Sailors Deputies and the complete subordination to all its orders.
2. The "Savage Division" as a counterrevolutionary military units cannot be tolerated with the bounds of Baku and its districts. Other national Moslem military units, as well as Armenian ones, should be either led out of the city or subordinated completely to the Soviet. Whole armed population must be under the control and check of the Soviet.
3. We demand the acceptance of immediate measures to open the railroads from Baku to Tbilisi and from Baku to Petrovsk.
— (Suny 1972, pp. 217–221)
The leaders of the Tartars at Baku were convinced that they would easily disarm the Armenian soldiers, because they were somewhat shut up in Baku, but they were sadly mistaken in their calculations. After a bloody battle which lasted a whole week the Armenians remained masters of the city and its oil wells. They suffered a loss of nearly 2,500 killed, while Tartars lost more than 10,000. The commander of the military forces of the Armenians was the same General Bagradouni, who, although he lost both of his legs during the fight, continued his duties until September 14, when the Armenians and the small number of Englishmen who came to their assistance, were forced to abandon Baku to the superior forces of the Turco-Tartars, and retreat toward the city of Enzeli in the northern Caucasus
— (Pasdermadjian 1918, pp. 193)
In the so called March Days of 1918, Baku descended into a mini-civil war, after the Bolsheviks declared war on Musavat Party and then stood by as Dashnak militias rampaged through the city, killing Azerbaijanis indiscriminately
Violence increased during the Civil War, with massacres of Azeri Turks – by the combined forced of Armenian Dashnaktsutiun party and the Bolsheviks
Muslims in Baku revolted in March 1918, but their uprising was suppressed by the city's Armenians
When in March 1918, Azerbaijanis revolted against the Baku Commune, Armenian Dashnaks and Bolshevik troops poured into the Azerbaijani quarters of the city and slaughtered thousands
After crushing a Muslim revolt in the city, the Bolshevik-led government, with its small Red Guard, was forced to rely on Armenian troops led by Dashnak officers
After the 'March Days', the Bolsheviks finally came to power and established their famous Baku Commune in April 1918
The oil-rich city of Baku had emerged as a stronghold of Bolshevism shortly after the October Russian Revolution, and friction between the Bolsheviks and the pan-Turkic Musavat party sparked a brief civil war in March 1918
Here is what Bakinsky Rabochy reports about it:
In the first half of January 1918, on the railway line between Tbilisi and Yelizavetpol, armed bands of Moslems many thousand strong, headed by members of the Yelizavetpol Moslem National Committee and with the support of an armoured train sent by the Transcaucasian Commissariat, forcibly disarmed a number of military units leaving for Russia. Thousands of Russian soldiers were killed or mutilated; the railway line was strewn with their corpses. They were deprived of about 15,000 rifles, some 70 machine guns and a score of artillery pieces.
— Joseph Stalin (26–27 March 1918). "Transcaucasian Counter-revolutionaries Under a Socialist Mask". Marxists Internet Archive.
