21.—Guatemala at War with Germany.
22.—Baron Von Richthofen, premier German flier, killed.
23.—British naval forces raid Zeebrugge in Belgium, German submarine base, and block channel.
May
7.—Nicaragua at war with Germany and her allies.
19.—Major Raoul Lufberry, famous American aviator, killed.
24.—Costa Rica at war with Germany and Austria-Hungary.
27.—Third German drive begins or Aisne-Marne front of 30 miles between Soissons and Rheims.
28.—Germans sweep on beyond the Chemin des Dames and cross the Vesle at Fismes.
28.—Cantigny taken by Americans in local attack.