Western Front
Aisne – NIVELLE OFFENSIVE (SECOND BATTLE OF THE AISNE) on 25-mile front (until April 20): Despite long preparatory bombardment and first French tank attack, from 0630 hours to nightfall 20 French divisions (6,731 infantry casualties in 3 divisions alone) have advanced c.600 yards, taking the 2nd line of German trenches south of Juvincourt and advance to the Aisne Canal against 15 German divisions instead of 6 miles anticipated.
Decimated by MG fire, Senegalese troops break and flee. Fifth Army’s 128 Schneider tanks bog down (32 knocked out), only few reach German third line. French troops suffer 40,000 casualties during the first day of the Second Battle of Aisne, a few days later up to c.100,000 instead of 15,000 planned for.
Nivelle belatedly confines effort to either flank of Chemin des Dames. Forewarned, Germans have inserted new First Army (F Below) from Somme between Third and Seventh Armies on the front of attack.
131 French aircraft (200 on paper) support Nivelle Offensive, 153 by April 21, but German fighters drive off French artillery and contact patrols. Bad weather also hampers.
At the beginning of the Nivelle offensive, French soldiers advanced against the Chemin des Dames heights, which was fortified by the Germans:
https://i0.wp.com/ww2-weapons.com/w...dames.jpg?ssl=1
Artois: Haig and his army commanders meet to plan next assault.
Naval and Overseas Operations
British submarine
C16 collides with the destroyer
Melampus and sinks, resulting in the deaths of all crew members:
https://twitter.com/CenturyAgoToday...8618496/photo/1
French liner
Sontay is sunk by the German submarine SM
U-33. The crew survives after boarding lifeboats:
https://twitter.com/CenturyAgoToday...6174592/photo/1
Asiatic and Egyptian Theaters
British advance towards Istabulat (12 miles south-east of Samarra).
Political, etc
Germany: Strikes (until April 23; but another source claims only a 1-day strike) in Berlin (217,000 workers) and Leipzig against bread ration cut (April 15).
Russia: Vladimir Lenin arrives at Petrograd; makes ‘April Theses‘ on April 17 speech to Petrograd Soviet.
United Kingdom: British food orders (that is, placed in the US) re: wheat, barley, and oats.
United States: Shipping Board’s Emergency Fleet chartered, 280,000 shipyard workers enrolled by April 20.
President Wilson issues a proclamation urging Americans to put their whole strength into the war:
http://www.firstworldwar.com/source/doyourbit.htm
President Wilson warns both citizens and alien residents against acts of treason and states that prosecution will be vigorous. [ed note: by this time, the definition of ‘treason’ was pretty broad, likely to encompass anything anyone said against the war, no matter how mild.