The united Sonbai realm is mentioned in the documents for the first time in 1649, when it was allied with the Portuguese. At that time it was a violently expansive kingdom that in the minds of the Dutch seemed set to subdue the entire Island of Timor. In 1655, however, Sonbai switched sides and started to persecute the Catholic converts and kill off any Portuguese they found. In the same year the Sonbai ruler Amanasi (or Ammasse) made a contract with the Dutch East Indies Company (VOC) in Kupang, together with Amabi. In the following few years the new alliance proved unable to stop the Portuguese, and suffered some bad defeats. In 1657 the Sonbai ruler was taken prisoner by the Portuguese, and in September next year a sizeable part of the Sonbai population fled to Kupang under the leadership of the executive regent of the Oematan family, Ama Tomananu.

This was the beginning of the split into two realms, Sonbai Kecil and Sonbai Besar. The VOC allowed the Sonbai Kecil to settle close to their fort in Kupang, where they became one of the five Company allies, the other being Kupang Helong, Amabi, Amfoan and Taebenu. It generally supported the Dutch administration loyally. The ruler was called Keizer (Emperor) by the Dutch, but he was mostly enjoying a ceremonial rather than actively ruling role. The executive powers lay in the hands of the Oematan family who, in the eighteenth century, split up in two branches called Saubaki and Loewis. An attempt was made in 1776-1783 to unite Sonbai Kecil with its sister kingdom Sonbai Besar, which lately left the sphere of Portugal in 1749 and allied with the VOC. The attempt proved futile however, and a new dynastic branch, Nisnoni, rose as rulers of Sonbai Kecil after 1783. They remained in charge until 1917, when the Dutch let Sonbai Kecil merge with four other kingdoms to form the larger zelfbesturend landschap (self-ruling territory) of Kupang. In the next year 1918 the old ruler of Sonbai Kecil became raja of Kupang. The family governed until 1955, when the new Indonesian republic altered the governance according to modern bureaucratic principles.

In the interior of West Timor Sonbai Besar remained a sizeable kingdom under Portuguese surveillance. While the captive ruler was allowed to remain on the throne, the executive government was handed over to the Kono family, whose main area of power became known as Amakono (later Miomaffo). The Portuguese likewise termed the ruler as Emperor, Emperador. There were devastating conflicts with the Portuguese overlords in 1711-13 and 1722, and in 1748-49 the current ruler Baob Sonbai left the Portuguese sphere and fled to Kupang with his subjects. This was one of the main reasons for the major military attack that the Portuguese mestiços launched against Kupang in 1749. The attack was smashingly defeated at the battle of Penfui, an incident that widened the Dutch sphere to almost entire West Timor. The new alliance with the VOC turned problematic, however, and in 1783 the Emperor Kau Sonbai left Kupang and reestablished an autonomous kingdom in the interior. This realm eventually eroded in the late nineteenth century, especially after 1885. The last ruler Sobe Sonbai III was captured by Dutch troops in 1906, putting a definite end to the kingdom.

SONBAI BESAR

Nai Dawan (son of Maromak Oan of Wehali)

Nai Natti (son)

Nai Faluk (son)

Nai Lele Sonbai (son)

Nai Tuklua Sonbai or Ama Tuan I (son) c. 1650-80

Nai Manas Sonbai (son) late 17th century

Nai Neno Sonbai or Dom Pedro Tomenu (son) fl. 1704-26

Nai Baob Sonbai I or Alfonso Salema (son) before 1749-1752

Don Bernardo [Nai Sobe Sonbai I?] (son) 1752-1760

Nai Tafin Sonbai or Albertus Johannes Taffy (brother) 1760-68

Nai Kau Sonbai or Alphonsus Adrianus (son) 1768-1819

Nai Sobe Sonbai II (son) 1819-1867

Nai Baob Sonbai II (son) 1867-c.1885

Nai Nasu Mollo (cousin, co-ruler) 1870-c.1885

Nai Sobe Sonbai III (son of Sobe Sonbai II) 1885-1906

SONBAI KECIL

Ama Tuan II (son of Nai Tuklua Sonbai) 1659-72

Bi Sonbai (daughter) 1682-1717

Bernardus Leu (son of Nai Neno Sonbai) 1717-1726

Corneo Leu (brother) 1728-48

Daniel Taffy Leu (brother) 1748-60

Jacobus Albertus Taffy (son of Bernardus Leu) 1760-76

Nai Kau Sonbai (of Sonbai Besar) 1776-83

Baki Bena or Bernardus Nisnoni (brother [cousin?] of Jacobus Albertus Taffy) 1783-95

Dirk Hendrik Aulasi (son?) 1795-98

Nube Bena or Pieter Nisnoni I (brother of Baki Bena) 1798-1820

Isu Baki (son of Baki Bena) 1820s

Ote Nuben Nisnoni (grandson of Nube Bena) fl. 1832

Babkas Nube Nisnoni or Pieter Nisnoni II (son of Nube Bena) ?-1839

Meis Babkas Nisnoni (son) 1839-60

Pieter Messi Nisnoni (son) 1860-74

Isu Nisnoni (brother) 1875-89

Said Meis Nisnoni (son) 1890-1902

Baki Bastian Meis Nisnoni (brother) 1905-11

Nicolaas Nisnoni (brother) 1911-17; Raja Kupang 1918-45

Alfonsus Nisnoni (son) Raja Kupang 1945-55

Sources are various pedigrees in unpublished Dutch memorandums, a manuscript by F.H. Fobia, Sonbai dalam kisah dan perjuangan (1984), and the archival Timor papers in Nationaal Archief, The Hague.