Birthdays
Antoinette Louisa Brown
Turns 38 on this date
John Brown
Turns 70 on this date
John Harris
Turns 73 on this date
Henry Bry Holmes
Turns 25 on this date
William Brown Norris
Turns 60 on this date
Events
| Education/Culture | At Epsom in southern England, Macaroni wins the eighty-fourth running of the Derby | 05/20/1863 |
| Battles/Soldiers | General John Schofield replaces abolitionist General Samuel Curtis in the Department of the Missouri | 05/20/1863 |
| Campaigns/Elections | In Cleveland, Ohio, thousands hear speeches at a mass meeting of the National Union League | 05/20/1863 |
| Campaigns/Elections | Indiana's Democrats hold a mass meeting at their convention in Indianapolis | 05/20/1863 |