- Period:
- American Civil War (1861-1865)
- Rank:
- 1st Lieutenant
- Unit:
- 24th Wisconsin Infantry, Union Army
- Awarded on:
- June 30th, 1890
"For extraordinary heroism on 25 November 1863, while serving with 24th Wisconsin Infantry, in action at Missionary Ridge, Tennessee. First Lieutenant MacArthur seized the Colors of his regiment at a critical moment and planted them on the captured works on the crest of Missionary Ridge."