1917 (MCMXVII, in Roman numerals) was a common 20th century year of the Gregorian Calendar, from the Age of Christ, and its Sunday letter was G (52 weeks), it began on a Monday and ended also on a Monday.
February 5 - Mexican Revolution: The Constitution of Mexico is sanctioned by the then President of Mexico Venustiano Carranza (President of Mexico between 1915 and 1920), this Constitution replaced the Mexican Constitution of 1857, and brought numerous advances to Mexico such as: salary minimum, right to strike, female vote, Separation of Church and State, Freedom of expression, etc. It was the first constitution in history to include so-called social rights, two years before the Weimar Constitution in 1919.
February 23 - In the Russian calendar, St Petersburg weavers and workers marched towards soldiers of the tsarist army, who surrendered their weapons and joined the rebels.
March 11 - First Direct Presidential Election takes place in Mexico in 1917 and Revolutionary Politician and Leader Venustiano Carranza is Elected Constitutional President of Mexico obtaining 98% of valid votes (727,305 votes out of 812,928) defeating Álvaro Obregón (gained 0.5% of votes) votes, that is, 4,008 of the 812,928 voters) and Pablo González Garza (he obtained 1.7% of the votes, that is, 11,615 of the 812,928 voters).
April 3 - On April 16, in the Russian calendar, the leader Lenin, who was in exile, returns to Russia and arrives in St. Petersburg, began to advocate the overthrow of the provisional government, the withdrawal of Russia from the war and the partition of land among the peasants.
April 26 - The Saint-Jean-de-Maurienne Agreement on the future partition of the Ottoman Empire between some of the First World War Allies is signed.
May 1 - Venustiano Carranza assumes the Presidency of Mexico
May 13th - First of six apparitions of Our Lady to three children, in Fátima - Portugal.
June 4 - The first Pulitzer Prize winners were chosen - 2 in the Journalism area (1 in the Reporting category and 1 in Editorial) and 2 in Literature (1 in History and 1 in Biography).
July 1 - Attempt to restore the monarchy in China to try to bring Pu Yi to power, by General Zhang Xun through a twelve-day coup.
July 9 - 1917 General Strike: death of anarchist José Martinez during a protest in São Paulo, is the trigger for the strike.
July 12 - Li Yuanhong regains power, re-establishing the Republic in China again.
July 17 - Li Yuanhong resigns as President of the Republic of China, and General Feng Guozhang, Vice President from 1916 to 1917, comes to power.
October 13 - The Virgin Mary reveals herself to be the Mother of God with the title of Our Lady of the Rosary and the Virgin herself makes the sun dance in the sky of Fatima, healing the sick and converting sinners, thus ending the cycle of apparitions in Fatima - Portugal
October 24 - The Russian Revolution begins: the Bolsheviks, led by Lenin and Trotsky, occupied the public buildings of the city of St. Petersburg, including the Winter Palace, and took power.
October 25 - President Wenceslau Braz declared a State of War on the German Empire.
December 6 - The cargo ships Mont-Blanc and Imo collide in Halifax, Canada, and an explosion caused by the Mont-Blanc cargo generates a tsunami, a mushroom of smoke and a shower of hot metal and glass.
December 12 - A train full of soldiers, about a thousand of them, derails near Modane station in France and about 800 soldiers die. Manuel García Prieto replaces Álvaro Figueroa y Torres Mendieta as president of the Spanish government.
Eduardo Dato y Iradier replaces Manuel García Prieto as