As the mughal empire began to decline, european powers took advantage of their weakness and began to extend control over growing areas of the indian subcontinent. eventually, one european power, would come to control almost all of india.

The British

Explanation:

Mughal Empire lost power due to many reasons, one of them is the loss of wars against other rival empires which led them to lose political control. Eventually, they needed protection from an European power, the British. The East India Company took charge of protecting the The Mugal Dynasty  gaining more militar on India. Finally Mugal Empire declined and on that time Great Bretain had already obtained full control of almost all of India.

which time period is this? or is this story fictional, i'm going to need more info to answer this question