The 9th New Jersey Infantry Volunteers was formed in August and September 1861 as a regiment of riflemen. This designation was very important since technology was shifting from smooth bore muskets to rifled weapons. Riflemen were expected to be more accurate and, therefore, more effective (deadly) on the battlefield. The regiment carried the Springfield Model 1861 rifled musket and wore the standard Union blue uniform.
The regiment drew men from around the state rather than recruiting from one county or region. Each company, however, was generally raised from one or two bordering counties. While New Jersey is not one of the larger states, there was no trouble achieving the authorized strength. If your ancestor is in this roster you should request his service or pension records from the National Archives.
There were 13 companies plus the Staff (S) company and the depot/recruiting company (U). The links below list the men in each company:
There is a memorial to the 9th New Jersey in New Bern, North Carolina to mark the Battle of Roanoke Island, their first major engagement, and subsequent service in garrison / occupation duty from 1862 to 1864. It was dedicated in 1905