Simplify the following text for a Grade 11 native English-speaking person.
Original: British Somaliland remained part of the Italian East Africa until March 1941 when the 1st\/2nd Punjab Regiment and the 3rd\/15th Punjab Regiment returned from Aden to re-occupy the territory .
Simplified: British Somaliland remained part of Italian East Africa for a matter of months . In March 1941 the 1st\/2nd Punjab Regiment and the 3rd\/15th Punjab Regiment -RCB- returned from Aden to re-occupy the territory during the East African Campaign .