Otis Dean, a private in Company E, 56th Massachusetts Infantry during the Civil War, was born on March 1, 1821 at Raynham, Massachusetts, the son of Chandler Robbins Dean and Abigail [Bissn?]. Dean married Augusta Dunbar (born October 1826) on January 4, 1848. By 1850, the Deans were living in Foxborough Massachusetts, where Otis Dean was employed as a boot-maker.

Dean enlisted in the Union Army as a private on December 30, 1863 and was mustered into Company E of the 56th Massachusetts on January 12, 1864. Wounded in battle at Peebles' Farm (September 30), Dean was captured by Confederate forces and held at Richmond. Paroled on October 8, 1864, Dean entered an army hospital at Annapolis, Maryland. He was granted a furlough later that month and spent several weeks recuperating at home and in the hospital at Readville, Massachusetts. After spending several additional weeks in hospitals at Annapolis and Germantown, Pennsylvania, Dean rejoined his regiment on March 20, 1865 and was discharged on June 15, 1865.

Returning to Foxborough, Dean by 1870 had become a farmer and the father of eight children (Mary, Frederick, Arthur, Edwin, William, Ernest, Harry and Herbert). The 1880 census found the family living in Arcadia Township, Iowa. Though no occupation was listed for Dean, three of his sons, living in the same household, were listed as farmers. By 1900, the Deans had again moved westward and were living in San Bernadino County, California. Otis Dean died on March 21, 1907; his wife, in 1911. Both are buried in Bellevue Cemetery of Ontario, San Bernadino County, California.

The 56th Massachusetts Infantry was recruited during the fall and winter of 1863 at Readville, Massachusetts. By February 1864, the entire regiment had been mustered into service. On March 20, the 56th left Massachusetts for Annapolis, Maryland, where it remained for approximately a month. Following the line of the Orange & Alexandria Railroad, the regiment arrived at Bealeton Station on April 30 and remained encamped there until May 4, when it joined the rest of the Army of the Potomac in the Wilderness Campaign. The 56th saw heavy action during the following month and participated in the assault against Petersburg in June and July 1864. The regiment participated in the battle of Weldon Railroad (August 19) and Peebles' Farm (September 30). In November, the 56th went into winter camp at Fort Davis and Fort Alexander Hays. The 56th joined in the final assault on Petersburg and the pursuit of Lee's forces and was mustered out on July 12, 1865.

Source:

Hancock, Daniel W. and Karen L. Hancock. "Hancock and Olson Family History." 26 March 2008 (http://hancockonline.net).