Three brothers - Curtis, Gilbert and Rufus Dean - and their siblings moved to Iowa from Cuyahoga County, Ohio, with their parents, Joseph and Sophia (Fay) Dean in July, 1842, and lived on a farm near Cascade in Dubuque County. One sibling, Joseph Dean, Jr., died in 1847 at twenty-two years of age and their father, Joseph Dean, died in 1857, the same year the Supreme Court issued its decision on the fate of the slave known as Dred Scott. Joseph and his son are buried in Cascade Community Cemetery (also known as Cascade City Cemetery).

After the election of Abraham Lincoln in 1860, tensions between the North and South escalated and on March 21, 1861, Confederate Vice President Alexander Stephens delivered his Cornerstone Speech saying, “our new government foundations are laid, its cornerstone rests, upon the great truth that the negro is not equal to the white man.” On April 12th, General Beauregard’s canon fired on Fort Sumter and war followed. Casualties were heavy and by the following year more volunteers were needed.

On July 9, 1862, Iowa’s Governor, Sam Kirkwood, received a telegram asking him to raise five regiments as part of the President’s call for 300,000 three-year men. If the state’s quota wasn’t raised voluntarily, it "would be made up by draft." Despite the Governor’s confidence that the quota would be reached, enlistments started slowly as "farmers were busy with the harvest, the war was much more serious than had been anticipated, and the first ebullition of military enthusiasm had subsided. Furthermore, disloyal sentiment was rampant in some parts of the State." All men between eighteen and forty-five were listed in preparation for a possible draft, a draft that wasn’t needed.

Rev. James Hill was an active recruiter in the Cascade area. On August 9th he was appointed 1st Lieutenant in what would be Company I of the state’s 21st regiment of volunteer infantry, a company with fellow Englishman David Greaves as Captain. On August 9th, Rev. Hill enrolled Curtis Dean and Sam Bates, on the 10th he enrolled John Goodrich and Emanuel Silence, on the 13th Martin Heitchew, on the 15th Ted Dare and Jasper Delong, on the 19th Joe Rogers, and on the 22nd Greenberry Halfhill. One article says Hill, who would later become the regiment’s Chaplain and its only Medal of Honor winner, was credited with enrolling 72 of the 101 men who were mustered in as a company on August 23d. Among them were Gilbert and Rufus Dean who had enlisted two days earlier.

With Gilbert and Rufus as Privates and Curtis as a 2d Sergeant and all ten companies of adequate strength, the regiment was mustered into service on September 9th at Dubuque’s Camp Franklin. A week later, on a rainy September 16th, they left camp at 10:00 a.m. and marched through town while families, friends and local residents watched. Women sent cakes and cheese and others tossed apples. From the levee at the foot of Jones Street soldiers boarded an overly crowded Henry Clay and two barges tied alongside, "packing ourselves like sardines in a box,” and started downstream. They spent their first night on Rock Island, resumed their trip the next day, debarked at Montrose due to low water levels, traveled by train to Keokuk, boarded the Hawkeye State, reached St. Louis on the 20th and were inspected on the 21st by Brigadier General John Wynn Davidson. That night the air was cold and men huddled under blankets as they sped along the Southwest Branch of the Pacific Railroad to its western terminus at Rolla, a town of about 600 residents.

They would spend the first six months of their service in Missouri where they were posted at Rolla, Salem, Houston, West Plains, Iron Mountain and the Mississippi River town of Ste. Genevieve where they camped on a ridge overlooking the river. In late March and early April, 1863, as space became available on river steamers, they were transported downriver with Company I leaving on the morning of March 27th. By April 6th all ten companies were united at Milliken’s Bend where General Grant was organizing a 30,000 man army with three corps led by Generals McClernand, McPherson and Sherman. Assigned to a brigade in McClernand’s corps, the able-bodied left the Bend about 9:00 a.m. on April 12th and, staying west of the river, started a slow movement south. Those not yet able to endure such a difficult march were left behind, but Curtis was with his comrades as they walked along dirt roads, crossed bayous and waded through swamps.

On April 30, 1863, they crossed from Disharoon’s Plantation in Louisiana to Bruinsburg, Mississippi, an old landing created in 1788 by Peter Bruin and his family. The first regiment to land was assigned to high ground above the river so they could sound an alarm if the enemy were sighted. The next regiment, the 21st Iowa, was ordered to take the lead as the point regiment for the entire army as it started inland, away from the river and the army’s base of supplies. About midnight near the Abram Shaifer house they drew fire from Confederate pickets. In darkness, gunfire was exchanged only briefly before both sides rested. On May 1st, Curtis participated in the Battle of Port Gibson, on May 16th he was present during the Battle of Champion Hill when General McClernand held the brigade out of action and on May 17th he participated in an assault at the Big Black River.

The regiment suffered heavy casualties in the assault and was allowed to remain to bury the dead and care for the wounded, including its colonel, Sam Merrill, who was seriously wounded while leading the charge. Other regiments moved to the rear of Vicksburg and on May19th participated in an unsuccessful assault. Grant spent the 20th and 21st constructing roads, improving communication lines, establishing a depot on the Yazoo, gathering food and supplies, conducting reconnaissance and planning a second assault. His men were anxious for a fight, he hoped to avoid a siege during the hot summer and he was fearful of Joe Johnston's forces behind him, forces that might be reinforced by Lee or Longstreet. Mindful of problems encountered during the first assault, ladders sixteen to twenty feet long were constructed, gunboats would keep the enemy annoyed during the night, artillery fire would begin at daylight on the 22nd and infantry would advance at 10:00 a.m.

By then the 21st Iowa had taken its position opposite the railroad redoubt and Fort Beauregard. When the order was given, Union soldiers, except for those held back as sharpshooters, moved forward, "the earth was black with their close columns" and, said Confederate General Stephen Lee, “there seemed to spring almost from the bowels of the earth dense masses of Federal troops, in numerous columns of attack, and with loud cheers and huzzahs, they rushed forward at a run with bayonets fixed, not firing a shot, headed for every salient along the Confederate lines." They were allowed by Lee "to approach unmolested to within good musket range, when every available gun was opened upon them with grape and canister, and the men, rising in the trenches, poured into their ranks volley after volley." The Northern soldiers were forced to fall back and their casualties were heavy.

In the 21st Iowa, twenty-three were killed in action, another twelve had fatal wounds, forty-three had non-fatal wounds and four were captured. Among the wounded were the three Dean brothers. The wounds suffered by Gilbert and Rufus were relatively slight but Cyrus, who was one of very few who had been able to enter the Confederate lines, sustained a severe chest wound. He was taken prisoner, treated in a Confederate hospital and, on July 3rd, died. The place of his burial has not been located.

Rufus was transferred to the Invalid Corps on May 15,1864, while Gilbert served his full term with the regiment and was mustered out on July 15, 1865, as a 1st Corporal.