Corpus Christi (Catholicism, 2008); World Biodiversity Day

• 1455 – Forces led by Richard, Duke of York and Richard, Earl of Warwick captured Lancastrian King Henry VI of England, beginning the Wars of the Roses with a Yorkist victory in the First Battle of St Albans.
• 1809 – War of the Fifth Coalition: Austrian forces under Archduke Charles (pictured) prevented Napoleon I and his French troops from crossing the Danube near Vienna at the Battle of Aspern-Essling.
• 1915 – Five trains were involved in a crash near Gretna Green, Scotland, killing 227 people and injuring 246 in the Quintinshill rail crash.
• 1964 – During a speech at the University of Michigan, U.S. President Lyndon B. Johnson presented the goals of his Great Society domestic social reforms to eliminate poverty and racial injustice.
• 1990 – The Yemen Arab Republic and the People's Democratic Republic of Yemen merged to become the Republic of Yemen.