Simplify the following text for a Grade 11 native English-speaking person.
Original: Although the Royal Navy is widely regarded as having been vital for the rise of the British Empire , and British dominance of the world , the British Army played an important role in the colonisation of India and other regions .
Simplified: Although the Royal Navy is widely regarded as having been vital for the rise of Empire , and British dominance of the world , the British Army played important roles in colonisation .