| 123rd Infantry Regiment | |
|---|---|
&sq=&lang=&file=File:123rd_Infantry_Regiment_COA.png) Coat of arms | |
| Active | 1917-1919, 1942-1946 |
| Country |  United States |
| Allegiance | Illinois |
| Branch | Illinois Army National Guard |
| Type | Infantry |
| Motto(s) | 1, 2, 3 Go! |
| Engagements | World War II |
| Insignia | |
| Distinctive unit insignia | &sq=&lang=&file=File:123_Inf_Rgt_DUI.png) |
| U.S. Infantry Regiments | ||||
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The 123rd Infantry Regiment was an infantry regiment of the United States Army.
The designation was first used in World War I for an Alabama National Guard unit part of the 31st Division.
In 1942, the 123rd was reactivated as a component of the Illinois Army National Guard and fought in World War II where it received acclaim for its jungle fighting against the Japanese in the Pacific Theater.