- May 5 Archibald Wavell, 1st Earl Wavell, British general, born in Colchester, Essex, England (d. 1950)
- May 6 José Ortega y Gasset, Spanish philosopher and author (The Revolt of the Masses), born in Madrid, Spain (d. 1955)
- May 7 Martin Albertz, German theologist (Jesus Christ's Church) and resistance fighter against the Nazi regime, born in Halle (Saale), Germany (d. 1956)
- May 13 Henk JFM Sneevliet, leader RSAP/editor Spartacus (Dutch-Indies)
- May 13 Georgios Papanikolaou, Greek doctor, inventor of the Pap smear (d. 1962)
- May 14 Jan Olieslagers, Belgian aviation pioneer (Antwerp Devil)
- May 14 Julian Eltinge, American vaudeville star, female impersonator, born in Newtownville, Massachusetts (d. d. 1941)
- May 18 Walter Gropius, architect (Bauhaus school of design), born in Berlin, Germany
- May 19 Henricus WJM Keuls, Dutch lawyer/poet (Dancing Lamp)
- May 20 Paul Arntzenius, Dutch painter, graphic artist and etcher, born in The Hague, Netherlands (d. 1965)
- May 25 Elsa Maxwell, American writer (Jack Paar Show), born in Keokuk, Iowa (d. 1963)
- May 28 Vinayak Damodar Savarkar, Indian independence activist and writer (The Indian War of Independence), born in Bhagur, India ((d. 1966)
- May 28 Clough Williams-Ellis, British architect known chiefly as the creator of the Italianate village of Portmeirion in North Wales, born in Gayton, Northamptonshire, England (d. 1978)
- May 31 Lauri Kristian Relander, 2nd President of Finland (1925-31), born in Kurkijoki, Finland (d. 1942)