The Major Change took place in Indian politics After 1990 was the beginning of the era of .... COALITION GOVERNMENT..... BEFORE....it..... the Same Party ruled both at a Central and in most of the state due to it,,,,,, state government do not exercise their power as autonomous Federal Unity.......,,,.... AFTER 1990 No Single party got clear majority in Lok Sabha ,,,,so alliance was formed with other many parties to form government at centre ..........,,.,.,..that made difficult for Central Government to dismiss the state government in an arbitrary manner.......

Major changes in Indian politics after 1990 that promoted the federal principles as well as improved the centre-state relationship in the country are as follows:

1. Economic Liberalization:
The economic liberalization policies of 1991 opened up the Indian economy to foreign investment and reduced the central government's control over the economy. This led to greater economic autonomy for the states and a shift towards a more federal system.

2. Constitutional Reforms:
The 73rd and 74th Constitutional Amendments in 1992 provided greater autonomy to the local bodies and promoted decentralization of power to the grassroots level. This led to greater participation of states in decision-making and promoted the federal principles.

3. Finance Commission Recommendations:
The recommendations of the Finance Commission regarding the distribution of resources between the Centre and states were implemented, leading to a more equitable distribution of resources and greater financial autonomy for the states.

4. Inter-State Council:
The establishment of the Inter-State Council in 1990 provided a platform for the Centre and states to discuss and resolve issues related to the federal structure of the country. This led to a more cooperative Centre-state relationship and greater respect for federal principles.

5. Coalition Politics:
The rise of coalition politics in the 1990s led to greater representation of regional parties in the Centre and increased participation of states in decision-making. This led to greater decentralization of power and a more federal system.

Overall, these changes led to a more federal system in India, with greater participation of states in decision-making and a more equitable distribution of resources between the Centre and states. The Centre-state relationship became more cooperative, with a greater respect for federal principles.