4th Mechanized Brigade ( United Kingdom ) 4th Mechanized Brigade ( The Black Rats ) is a British Army brigade formation , currently based in Catterick , North Yorkshire as part of 3rd ( UK ) Mechanised Division . The brigade , now known as the ' Black Rats ' , was formed in 1939 and fought in the Western Desert Campaign . The Black Rats were subsequently involved in the Invasion of Sicily and fighting in Italy before taking part in the Battle of Normandy and the advance through Belgium , Holland and into Germany . More recently , the Brigade took part in the First Gulf War and completed a number of tours to the Balkans during the 1990s . The Black Rats have since deployed twice to Iraq and once before to Afghanistan for Operation Herrick 12 in 2010 . The Brigade returned to Helmand Province , Afghanistan in October 2012 for Operation Herrick 17 to take over as the lead formation of British troops . The roulement tour saw the brigade working in support of the Afghan Army ' s 3 / 215 Brigade and elements of the Afghan National Police . History . World War II . In 1939 , at the start of the Second World War this brigade changed its title from " Heavy Armoured Brigade ( Egypt ) " to 4th Armoured Brigade . On 27 July 1941 it handed over its units to the 1st Army Tank Brigade and received new units from Egypt . It was reformed again when the HQ arrived in Sicily and it took control of new units there . The 4th Armoured Brigade saw service in North Africa , Sicily and Italy and in the North West Europe Campaign . Although it served under many different formations it was most famous as part of the 7th Armoured Division , the Desert Rats . The Brigade left 7th Armoured Division in North Africa in 1943 for the Allied Invasion Force for Normandy . In June 1944 Brigade troops landed in Normandy and was the first Brigade to cross the Rhine into Germany . Cold War Era . The Brigade spent many years in Germany as part of the British Army of the Rhine . The Brigade deployed to the First Gulf War on Operation Granby in 1990 / 91 and was involved in the liberation of Kuwait . It moved to Osnabrück in 1991 to replace 12th Armoured Brigade as part of 1st ( UK ) Armoured Division . Post - Cold War . 4th Armoured Brigade deployed to Bosnia in October 1995 as UNPROFOR HQ Sector South - West and subsequently as the leading UK element of the NATO Implementation Force ( IFOR ) . On its return to the United Kingdom it was transferred from 1st ( UK ) Armoured Division to 3rd ( UK ) Mechanised Division . The Black Rats have since deployed twice to Iraq and once before to Afghanistan for Operation Herrick 12 in 2010 . The Brigade returned to Helmand Province , Afghanistan in October 2012 for Operation Herrick 17 to take over as the lead formation of British troops . The roulement tour saw the brigade working in support of the Afghan Army ' s 3 / 215 Brigade and elements of the Afghan National Police . Under Army 2020 , it will lose its armour and convert to an infantry brigade . World War II Commanders . During World War II Brigade Commanders . Recent commanders have included : Notable former soldiers . Former BBC Motor sports commentator Murray Walker served with 4th Armoured Brigade during the Second World War as a member of The Royal Scots Greys . After the war he started a motorcycle club , organising trials and scrambles for the soldiers within the Brigade .