- 585 BC Solar eclipse, as predicted by Greek philosopher Thales, while Lydians at war with the Medes leads to a truce. One of the cardinal dates from which other dates calculated.
- 1431 Joan of Arc is accused of relapsing into heresy by donning male clothing again, providing justification for her execution
- 1588 Spanish Armada under the Duke of Medina-Sidonia departs Lisbon to invade England
- 1830 US Congress authorizes native Indian to be removed from all states to the western prairie
- 1936 Alan Turing submits "On Computable Numbers" for publication, in which he set out the theoretical basis for modern computers.
- 1972 White House "plumbers" first break in at the Democratic National Headquarters at Watergate Complex in Washington D.C.
Near Callander, Ontario, the Dionne quintuplets are born to Olivia and Elzire Dionne, later becoming the first quintuplets to survive infancy
On May 28, 1934
Monkeys Able & Baker zoom 300 miles (500 km) into space on Jupiter missile, become 1st animals retrieved from a space mission
On May 28, 1959