Historical Events
- May 3 Battle at Tolentino: Austria beats King Joachim of Naples
- May 16 The Governor of New South Wales, Lachlan Macquarie, officially names the town of Blackheath in the upper Blue Mountains
- May 24 George Evans discovers Lachlan River, Australia
Famous Birthdays
- May 3 Hermanus Willem Witteveen, Dutch theologist, born in Boornbergum, Netherlands (d. 1884)
- May 5 Eugène Marin Labiche, French playwright (The Italian Straw Hat), born in Paris (d. 1888)
- May 8 Jean-Delphin Alard, French violinist and composer, born in Bayonne, France (d. 1888)
- May 18 Thomas Stanhope Bocock, rep (Confederacy), (d. 1891)
- May 19 John Gross Barnard, American Brevet Major General (Union Army), born in Sheffield, Massachusetts (d. 1882)
- May 27 Henry Parkes, Australian politician (longest non-consecutive Premier of the Colony of New South Wales), born in Canley, Warwickshire, England (d. 1896)
