Around 2300 BC, some city-states appeared in the Indus Valley. Harappa and Mohenjo are the most famous scenic spots. Mohenjo's heroes are divided into acropolis and downtown. The Acropolis has huge public buildings and granaries, and the city center has well-planned, vertically intersecting streets and lanes and a set of sewer networks.

After15th century BC, Aryans from Central Asia invaded India one after another and established some small slave countries in the Indus River and Ganges River basins. They invented 10 number symbols including zero, and also invented the current universal notation.

In the 6th century BC, India's caste system caused strong dissatisfaction and sharp social contradictions. In this case, Sakyamuni founded Buddhism. Buddhism advocates "all beings are equal", advocates eliminating desires to get rid of suffering, and teaches people patience and obedience to enter the "paradise". Because Buddhism teaches patience and obedience, it is conducive to consolidating rule. Therefore, in the middle of the 3rd century BC, Asoka, who lived in India, designated Buddhism as the state religion. He built temples and pagodas extensively in Inner Mongolia, and Buddhism got great development. Since then. Buddhism has gradually developed into a worldwide religion.

There are simpler things:

The Indus River is the largest river in India, the Ganges River is the second largest, and Buddhism is the state religion. It is the first country in the world to discover mathematical symbols, and its representatives are Mohenjo, the hero of the legal circle and Sakyamuni.