I want to know the answer to the following question:
What caused the downfall of the downfall of the the original kingdom in Myanmar?
All the background I'm provided with is that "In the 9th century, the Bamar people entered the upper Irrawaddy valley and, following the establishment of the Pagan Kingdom in the 1050s, the Burmese language, culture and Theravada Buddhism slowly became dominant in the country.". Is that enough to answer the question?