Birthdays
Noah Bowlus
Turns 31 on this date
Gordon Newell Mott
Turns 48 on this date
David Harrison Walton
Turns 30 on this date
Amiel Weeks Whipple
Turns 43 on this date
Events
| US/the World | Former Neapolitan provinces, including Sicily, vote overwhelmingly to join a united Italy | 10/21/1860 |
| US/the World | In Italy, Piedmontese forces sweep aside Neapolitan resistance and advance on Capua | 10/21/1860 |
| Campaigns/Elections | Stephen Douglas makes his final campaign tour, through the Deep South |
10/19/1860 to 10/28/1860 |
Documents
| Newspaper | New York Herald, “American Sensations During 1860,” October 21, 1860 | 10/21/1860 |