Which event significantly contributed to the differences between the early and later states in South Asia?

The significant contribution to the differences between early and later states in South Asia is primarily attributed to the interactions resulting from the spread of Islam. During the medieval period, the advent of Islam introduced new political, economic, and cultural dynamics to the subcontinent. As Islamic empires, such as the Delhi Sultanate and later the Mughal Empire, expanded their influence, they brought diverse traditions and governance practices that contrasted with the indigenous Hindu kingdoms.

The spread of Islam facilitated new administrative structures, trade networks, and cultural exchanges, leading to a fusion of Islamic and local customs. This interaction not only transformed the political landscape but also affected social practices, artistic expressions, and economic activities. Consequently, the nature of states that emerged during and after this period was greatly marked by these Islamic influences, distinguishing them from the earlier Hindu-dominated states that predominantly characterized the region before the arrival of Islam.

In contrast, while the establishment of trade routes by the British Empire, the rise of dynasties like the Gupta and Chola without external influence, and the weakening of local governance during the Mughal Empire all played roles in shaping the history of South Asia, they don't capture the transformative impact that the spread of Islam had on state formation and evolution in the region.