Answer by Raakhee V. Menon:
Thank you for the A2A.
has outlined the main reasons quite well. The lack of an able ruler with the same power of organization and administrative excellence as Emperor Ashoka would have eventually led to the downfall of the once consolidated empire. Ashoka was followed for 50 years by a succession of weaker kings who got weaker with every succeeding monarch.
There is also the additional factor that almost all of Emperor Ashoka’s successors were Buddhists and were pious followers of its doctrines. Yes, it is true that the major part of Emperor Ashoka’s reign was one of peace and spreading of the message of Buddha. But Ashoka’s might and valor was well known. It was common knowledge that he was a mighty warrior who had deliberately renounced violence. He was, nevertheless, not someone to mess around with. After the death of Ashoka, however, the continuing peacekeeping strategies of subsequent kings were seen as a sign of weakness by many, and gradually the mighty empire and its territories began to shrink at an alarming rate.
The last ruler of the Mauryan empire (which was fast deteriorating from its erstwhile grandeur) was assassinated in 185 BCE during a military parade by Brahmin general Pushyamitra Shunga, commander-in-chief of his guard, who then took over the throne and established the Shunga dynasty.
Again Pushyamitra Shunga was probably the strongest of the Shunga kings as well. After his rule of 36 years, there were just ten emperors who succeeded him. They sadly took the same deterioration path as the mauryas did before them. The last ruler of the Shunga dynasty, Devabhuti, was overthrown by Vasudeva of the Kanva dynasty in 75 BC. Vasudeva Kanva was originally an Amatya (minister) of last Shunga ruler Devabhuti. Bana’s Harshacharita informs us that he came to power after the death of Devabhuti by a daughter of his slave woman disguised as his queen.
The Kanva dynasty lasted even lesser than the Shunga dynasty – it had just four rulers, the last of whom was overthrown by the Shatavahanas.
And the kingdoms further fragmented into many many more kingdoms, feudatories, etc. It is but common knowledge that at the time of the British withdrawal, 565were officially recognized in the Indian subcontinent, apart from thousands of zamindaris and jagirs.
Teaching in schools about the formation and decline of so many small kingdoms and princely states is mostly a futile practice. I believe that is why schools usually teach about the more prominent empires and ruling dynasties, and then move on to the entry of the East India Company into the subcontinent.