The Rakhing Razawon Houng (Old History of Arakan) was one of the seminal reference sources for early 20th century history books on Arakan. However, the source was lost until rediscovery by the author, of a mid-19th century copy in the Department of Archaeology (Yangon)’s archive. The manuscript describes not only the local dynastic histories, but alliance and relationships, as well as wars, with neighbouring states or cultures such as Pyu (Sri Ksetra), Bagan, Bago, Ava, Mughal, Tai spanning the first to second millennium CE. Further sections record the legendary history of solar and lunar dynasties, as well as stories related to Mahamuni cult and the traditional arrival of the Buddha. The development of Buddhism is further described in the religious diplomacy with Sri Lanka. Finally, the key sites in the urban architecture of Mrauk-U are documented. While there has been recent research on the ancient Arakan culture with the preparation of the nomination dossier on Mrauk-U submitted in 2021 to the UNESCO World Heritage Committee by the Department of Archaeology, Myanmar, much remains to be understood about the art, archaeology and changing landscape this region. The present paper draws on the Rakhaing Razawon Houng to give new perspectives on the changing society and religious practice reflected in the exchanges and conflicts with neighbouring domestic and regional cultures.