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Early civilisations in Myanmar included the Tibeto-Burman-speaking Pyu city-states in Upper Burma and the Mon kingdoms in Lower Burma.[12] In the 9th century, the Bamar individuals joined the upper Irrawaddy area and, pursuing the establishment of the Pagan Kingdom in the 1050s, the Burmese vocabulary, tradition and Theravada Buddhism slowly became dominant in the country. The Kingdom fell due to the Mongol invasions and states that were warring emerged.