Complex sentence: In 1806, the first casualties of the Battle of Blaauwberg drowned at Bloubergstrand when the British forces defeated the defending Dutch forces and subsequently occupied the whole of the Cape Colony.
Split into simpler sentences: In 1806, the first casualties of the Battle of Blaauwberg drowned at Bloubergstrand. The invading British forces defeated the defending Dutch forces and subsequently occupied the whole of the Cape Colony.