World War One Diary for Saturday, May 31, 1919:
USA – Aviation: First Transatlantic air crossing completed at Plymouth by USN Curtiss NC4 flying-boat from Rockaway, New York (left May 8, covered 3,150 nm in under 44hrs Newfoundland-Lisbon May 25-27).
Germany: Allied note to Germans to retreat their troops in Baltic States.
Baltic: 3 Royal Navy cruisers and 6 destroyers drive several Soviet warships back into Kronstadt. Reds withdraw from Gulf of Riga.