Birthdays
John Calvin Brown
Turns 39 on this date
George Huntington Browne
Turns 55 on this date
Wilmer Coffman
Turns 26 on this date
John Wesley Frazer
Turns 39 on this date
Joseph Holt
Turns 59 on this date
Charles Jones Jenkins
Turns 61 on this date
Ward Hill Lamon
Turns 38 on this date
Charles Sumner
Turns 55 on this date
Events
| US/the World | As Chile and Peru face Spain, a large public meeting is held in New York in support of the Monroe Doctrine | 01/06/1866 |
| US/the World | Queen Victoria emerges from mourning to open the British Parliament, her first public function since 1861. | 01/06/1866 |
| Legal/Political | The first session of the 39th Congress returns from a two-week holiday recess | 01/06/1866 |
| Crime/Disasters | Thieves rob a New Haven Railway train express car as it rolls through the night to Boston | 01/06/1866 |