In Events:

May 13th 1559 Excavated corpse of heretic David Jorisz burned in Basel
May 13th 1568 Mary Queen of Scots is defeated by English at battle of Langside
May 13th 1588 King Henri III flees Paris
May 13th 1767 Mozart's opera "Apollo et Hyacinthus," premieres in Salzburg
May 13th 1777 University library at Vienna opens ..
May 13th 1835 1st foreign embassy in Hawaii forms
May 13th 1846 US declares war on Mexico, 2 months after fighting begins
May 13th 1888 Princess Isabel of Brazil signs "Lei Aurā€ša" abolishing slavery
May 13th 1911 NY Giant Fred Merkle is 1st to get 6 RBIs in an inning (1st)
May 13th 1913 1st 4 engine aircraft built & flown (Igor Sikorsky-Russia)
May 13th 1926 German govt of Luther falls
May 13th 1934 Great dustbowl storm
May 13th 1940 Churchill says I have nothing to offer but blood, toil, tears & sweat
May 13th 1958 Rioters attack US VP Nixon in Venezuela
May 13th 1968 1,000,000 French demonstrate against De Gaulle & Pompidou
May 13th 1978 Henry Rono of Kenya sets record for 3,000 m steeplechase (8:05.4) (Why oh why didn't Obama just take up running?)
May 13th 1992 Final episode of "Night Court" airs on NBC-TV
May 13th 1992 Frank Stallone beats Geraldo Rivera in boxing on Howard Stern Show