Wikipedia:Selected anniversaries/May 4
On May 4:
- 1471 - Wars of the Roses: Edward IV defeated a Lancastrian Army in the Battle of Tewkesbury.
- 1886 - The Haymarket Square Riot started with a bomb throwing at a labor rally in Chicago, Illinois.
- 1919 - The May Fourth Movement was launched in China.
- 1970 - The Ohio National Guard shot students at Kent State protesting the United States' invasion of Cambodia.
- 1979 - Margaret Thatcher became the first female Prime Minister of the United Kingdom.