The East India Company was founded in England in 1599 and soon began building trading warehouses in India.
India wasn't a united country and there were many small states. The EIC sometimes asked for perms. to trade but sometimes didn't.
May we trade?
At the same time, the French had their own EIC and sparked a war between France and Britain in 1700.
In 1757 Robert Clive persuaded an Indian general to fight with him and overthrow Siraj-ud-Daula the ruler of Bengal. The battle was won and Siraj-ud-Daula was captured and killed. This gave Britain control over Bengal.
Robert Clive was treated as a hero in England. He was sent back in 1765 and slowly took over India bit by bit and defeated the French.
By the 1850s, the British ruled about 60% of India. The British banned traditional Indian ceremonies. Some people in India disliked British rule.