1865 June Am Civil War Gazette

- Trial of the Assassins continues in Washington
- Detailed transcripts of the trial of the assassins of Abraham Lincoln continues

- Red River Disaster
- The steamboat Kentucky sinks, killing many Confederate prisoners-of-war

- Colorado War (Colorado Territory)
- Raids at Dry Creek (Wyoming)
- Engagement at Platte Bridge Station
- Raid at Sage Creek Station
- Engagement in the Yellowstone River Valley
- Raid on Col. Moonlight's horse herd

- Gen. John S. Mosby (CSA) surrenders in Lynchburg

- Gen. Kirby Smith signs surrender of the Confederate Trans-Mississippi Department near Galveston, Texas

- Gen. Stand Watie surrenders at Fort Towson in the Choctaw Nation
- Last Confederate general to surrender

- U.S. Army
- Gen. Terry replaces Gen. Ord as commander of the Department of Virginia
- Reorganization of the U.S. Army into 5 divisions and 18 geographical departments
- Department and Army of the Potomac is disbanded
- Military Division of the Atlantic created
- Contained Departments of the East, Middle, Virginia, North Carolina and South Carolina
- Gen. Meade appointed commander
- Department of the East
- Gen. Hooker replaces Gen. Dix as commander
- Department of the Northwest is merged into the Department of the Missouri
- Gen. W.T. Sherman replaces Gen. Pope as commander of the Military Division of the Missouri
- Military Division of the Pacific created
- Contained Departments of the Columbia, California, and New Mexico
- Gen. Halleck appointed commander
- District of California raised to Department
- Commanded by Col. McGarry until Gen. McDowell could take command

- Gen. Gordon Granger reads General Order No. 3 in Galveston, Texas
- Origin of the 1866 Juneteenth celebration

- Viroqua tornado (Wisconsin)