Complex sentence: Originally formed as the Somali Guard Battalion, and tasked with defending the border between British and French Somaliland, it quickly rose in size and importance and became the Somali Companies in June 1942 before being renamed finally to the Somaliland Scouts in August 1943.
Split into simpler sentences: Originally formed as the Somali Guard Battalion, and tasked with defending the border between British and French Somaliland, the brigade quickly rose in size and importance. It later became the Somali Companies in June 1942, before finally being renamed to the Somaliland Scouts in August 1943.