66th Armor Regiment ( United States ) The 66th Armor Regiment is the oldest Armored unit in the United States Army , tracing its lineage to the beginning of the Tank Service in February 1918 under the command of Col . George S . Patton ; it was first activated in the Regular Army as the 66th Infantry Regiment ( Light Tanks ) . Current Disposition . Two battalions of the regiment are still in service in the Regular Army . Regimental history . World War I . What would become the 66th Armored Regiment was originally organized in World War I as the 1st and 2d Provisional Brigades , United States Tank Corps . The brigades participated in the battle of St . Mihiel , France , attached to the 1st Infantry Division , and in the Meuse - Argonne and the Somme Offensives . Just before the Armistice with Germany , the brigades were redesignated respectively the 304th and 305th Brigades , Tank Corps on 6 November 1918 . The casualties among the officers and men were severe during the short period the regiment participated in combat and their valor was recognized by General John J . Pershing in the following words : " The percentage of casualties among the officers and men tells the tale of splendid morale and gallantry in action and their unselfish devotion to duty " . The regiment ' s Organization Day was chosen as September 12 to commemorate its baptism of fire at St . Mihiel . The Headquarters and Headquarters Companies ( HHC ) of the 304th and 305th Tank Brigades transferred in 1919 to Camp Meade , Maryland and consolidated on 22 June 1921 , reorganized and redesignated as HHC , 1st Tank Group . This organization reorganized and was redesignated HHC , 1st Tank Regiment on 1 September 1929 , as the 66th Infantry Regiment ( Light Tanks ) on 25 October 1932 , and as the 66th Armored Regiment on 15 July 1940 , to become part of the newly formed 2nd Armored Division , stationed at Fort Benning , Georgia . World War II . In December 1942 , the regiment participated in the amphibious invasion of French Morocco in North Africa and led the division ' s entry into Casablanca . The regiment participated in the invasion of Sicily and through fierce fighting earned the unit six battle streamers during the war . In 1944 , the three battalions of the regiment went into action on the European Continent , beginning landing on Omaha Beach on D + 3 ( 9 June 1944 . ) Four days later the regiment ( as part of Combat Command A of the 2nd Armored Division ) fought through elements of the German 6th Fallschirmjager Regiment and elements of the 17th SS Panzergrenadier Division southwest of Carentan , France at the Battle of Bloody Gulch . Later progress was also initially difficult in combat against elements of the newly arrived 116th Panzer Division and surviving elements of the Panzer Lehr Division . In a difficult battle in the streets of the village of Percy and on surrounding high ground on 30 July , against some of the eight Panthers Generalleutnant Fritz Bayerlein had found and rallied from workshops at neighbouring Villebaudon on 28 July , the 3 / 66th was to lose 13 tanks and was forced to pull out of the village losing another five tanks outside Percy to heavy Nebelwerfer and other mortar fire . On 31 July 3 / 66th was down to only 24 operational tanks . The regiment fought across France to the German border with the rest of the division and the U . S . Third Army , but was diverted north to counter the German advance during the Battle of the Bulge , assisting in the destruction of the 2nd Panzer Division and capturing Houffalize , Belgium . As a result of its exemplary conduct in the liberation of Belgium , the regiment was twice cited in the Order of the Day of the Belgian Army . Captain James M . Burt , the commander of B Company , 66th Armored Regiment , was awarded the Medal of Honor for his heroism during the Battle of Aachen in October 1944 . Captain Burt later served as Honorary Colonel of the Regiment . Cold War . Following the war , elements of the 66th and other units of the 2nd Armored Division were selected to occupy the American sector of Berlin and serve as the first American troops to enter the fallen German capital . During the Korean War , an offspring of the 66th fought under the designation " 6th Tank Battalion " . During the war , the sixth won seven battle streamers and the Korean Presidential Unit Citation . These honors were awarded to the 66th Armored Regiment when the 6th Tank Battalion was deactivated after the conflict . Throughout the Cold War , the four battalions of the regiment served in the 2nd Armored Division at Ft . Hood , Texas , and as part of the 2nd Armored Division ( Forward ) in the Federal Republic of Germany . Desert Storm . In 1991 , during Operation Desert Storm , the regiment again proved its worth by assisting in the liberation of Kuwait and the defeat of the Iraqi army . The 2nd and 3rd battalions of the regiment , stationed in Germany as part of the 2nd Armored Division ( Forward ) , deployed and fought under the operational control of the 1st Infantry Division . The 4th battalion , along with the 3d ( Phantom ) Brigade of the 3rd Infantry Division , was attached to the 1st Armored Division . The Phantom Brigade became the 1st Armor ' s lead brigade for VII Corps ' " left hook " to smash the Iraqi Republican Guard divisions . In the Spring of 1995 , the 1st Battalion of the 66th was assigned to assist over 5 , 000 Cuban and Haitian refugees interned at Guantanamo Bay , Cuba . Global War on Terror . The 1st and 3rd Battalions have deployed to Iraq in support of Operation Iraqi Freedom and Afghanistan in support of Operation Enduring Freedom . 3 – 66 Armor was deployed to Operation Iraqi Freedom for 2008 – 2009 and 1 - 66 Armor deployed shortly after 3 - 66 Armor to Operation Iraqi Freedom from 2008 - 2009 as well . This was the last tour of duty for 1 - 66 Armor BN while stationed at Fort Hood , TX before relocating to Fort Carson , CO . 1 - 66 Armor BN was then deployed to Operation Enduring Freedom from 2010 - 2011 , as part of the surge in the volatile Arghandab River Valley west of Kandahar City in RC - South . 3 - 66 Armor BN was recently deployed to Operation Enduring Freedom from 2011 - 2012 to Paktika Province in RC - East . Motto : Sempre in Hostes . ( Always into the enemy ) .