Negara Brunei Darussalam is one of the ancient kingdoms of Southeast Asia. It has a rich history but many parts that history are missing and have not been found and written down due to the lack of concrete evidence and data, especially as regards to the Pre-XVII century period. However the evidences of these early period such as monuments, artifacts, coinage, documents, genealogies, manuscripts and oral traditional do provide us with some little information and sketchy pictures of Brunei's past.

Thus book Tarsilah Brunei: The Early History of Brunei Up To 1432 AD is a translation of the Malay work entitled Tarsilah Brunei: Sejarah Awal dan Perkembangan Islam, Volume I, first published in 1990. It has been edited for clarity and incorporated data obtained from historical researches on the early history of Brunei undertaken by the author since it was first published; and contains arguments and even conclusion different from the 1990 edition. This book is the first volume of several more volumes on the history of Brunei. This volume discusses the Early History of Brunei, the Original of the Brunei Sultanate, the Coming and Spread of Islam to Brunei, and also the history of the third Sultan of Brunei, Sultan Sharif Ali.

The first chapter explains about the early history and the origins of the name Brunei, its geographical location and its relation with neighboring countries. Yang connections/ties with the Rajas of Malay Archipelago. Chapter III however, besides explaining the coming of Islam to Nusantara and the early countries that embraced Islam, also examines the earliest known dates Brunei accepted Islam and Brunei's role in the spread of Islam to the region. Chapter VI traces the genealogy of the Sultan Sharif Ali known as Sultan Berkat - the Blessed Ruler, whose descendants can be traced to Prophet Muhammad, May the Blessing of Allah and Peace be upon him, and his role in the development of Brunei, especially in the administration and spread of Islam in Brunei.

With the publication of this book Tarsilah Brunei: The Early History of Brunei up to 1432 AD. It is hoped that is could broaden the scope of the study on the history of Brunei, not merely for local consumption, but also for use as reference work for other historians and students of history from outside the country interested in doing research on the Brunei Sultanate.