In 1939, the brigade was a 1st Line Territorial Army Brigade stationed in the United Kingdom. It was assigned to Eastern Command defending the south-eastern portion of the country. Equipment shortages prevented it from receiving any significant numbers of modern tanks; obsolete Vickers Medium Mark II and Mk II Light Tanks comprising most of the armour on hand until after the Battle of Dunkirk. Shortly after that battle, the brigade HQ was pulled back to Salisbury Plain, although each tank battalion was detailed as a mobile reserve for the infantry divisions holding the coastline. Each regiment could only form a single mobile squadron, the remaining two serving as infantry.