WHAT ALL HAPPENED FEBRUARY TO SEPTEMBER 1917
Find out what all happened February to September 1917

World War I: The Battle of Polygon Wood begins. (26. September 1917)

World War I: The United States breaks off diplomatic relations with Germany a day after the latter announced a new policy of unrestricted submarine warfare. (3. February 1917)

The enactment of the Jones-Shafroth Act grants Puerto Ricans United States citizenship. (2. March 1917)

Ten Suffragettes are arrested while picketing the White House. (28. August 1917)

The United States takes possession of the Danish West Indies after paying $25 million to Denmark, and renames the territory the United States Virgin Islands. (31. March 1917)

World War I: The United States declares war on Germany (see President Woodrow Wilson's address to Congress). (6. April 1917)

King George V issues a Proclamation stating that the male line descendants of the British Royal Family will bear the surname Windsor. (17. July 1917)

World War I: Baghdad falls to Anglo-Indian forces commanded by General Stanley Maude. (11. March 1917)

The U.S. government releases the unencrypted text of the Zimmermann Telegram to the public. (1. March 1917)

In a game against the Washington Senators, Boston Red Sox pitcher Ernie Shore retires 26 batters in a row after replacing Babe Ruth, who had been ejected for punching the umpire. (23. June 1917)

The first U.S. troops arrive in France to fight alongside Britain and France against Germany in World War I. (26. June 1917)

The current constitution of Mexico is adopted, establishing a federal republic with powers separated into independent executive, legislative, and judicial branches. (5. February 1917)

World War I: Battle of Messines – Allied soldiers detonated ammonal mines underneath German trenches at Messines Ridge, killing 10,000 German troops. (7. June 1917)

Vietnamese prison guards led by Trịnh Văn Cấn mutiny at the Thái Nguyên penitentiary against local French authority. (30. August 1917)

The East St. Louis Riots end. (2. July 1917)

Some provinces and cities in the Philippines were incorporated due to the ratification of Act No. 2711 or the Administrative Code of the Philippines. (10. March 1917)

World War I: Greece declares war on the Central Powers. (30. June 1917)

Russia is officially proclaimed a republic. (14. September 1917)

Vladimir Lenin returns to Petrograd, Russia from exile in Switzerland. (16. April 1917)

The Georgian Orthodox Church restores its autocephaly abolished by Imperial Russia in 1811. (25. March 1917)