He enrolled Company K and was elected captain of that company at its organization, commanded the company at the battle of Perryville, through the Kentucky and Murfreesboro campaigns, and was promoted to be major of the regiment April 6, 1863. He was appointed provost marshal when the brigade was assigned to garrison duty at Murfreesboro, Tenn., but returned to duty with the regiment when the brigade was ordered to Nashville to prepare for an active campaign at the front. When In the assault on Kennesaw mountain .Colonel Dilworth was called to command the brigade, the command of the Eighty-fifth devolved upon Major Rider. He retained command of the regiment until disabled by a gun shot wound in the head at the assault upon the enemy's lines at Jonesboro, Ga. Recovering, at least partially, from his wound he resumed command of the regiment, which he led in the march to the sea. He resigned at Savannah, Ga., December 19, 1864.
Returning to Havana he resumed the practice of medicine, which he continued until 1880, when he removed to Mount Ayr, Iowa. In 1884 he retired from the active practice of his profession, but resided in Mount Ayr to the time of his death, which occurred on November 14, 1899.
Name: RIDER, ROBERT G. Rank; CPT. Company; K. Unit; 85 IL US INF. Age: 32. Joined When: JUL 18, 1862. Joined Where; MASON CO, IL. Period; 3 YRS. Muster In; AUG 27, 1862. Muster In Where; PEORIA, IL. Remarks: PROMOTED MAJOR MAY 30, 1863.
Name; RIDER, ROBERT G. Rank: MAJ. Company; HQ. Unit; 85 IL US INF. age: 32 joined When: MAY 30, 1863. Joined Where: BRENTWOOD, TN. Joined By Whom; GOV OF ILL. Period: 3 YRS. Muster In: MAY 30, 1863. Muster In Where; NASHVILLE, TN. Remarks: RESIGNED DEC 19, 1864.