The Burmese left no garrisons behind, and within a few months various small Thai principalities were formed, all claiming the inheritance of the King of Ayutthaya. However a general of half Chinese blood, Phya Taksin, soon defeated all his rivals, and as early as 1769, with the aid of the few loyal survivors of the catastrophe, he proclaimed himself King of the re-united land. For his new residence he selected Dhonburi on the right bank of the Menam, opposite Bangkok. Under his reign the reconquest of the vassal states begun; Chiang Mai was finally regained from the Burmese in 1775, and Luang Prabang and Vientiane had to recognise Thai suzerainty.
In his later years Taksin fell victim to religious mania, and in a palace revolution of his ministers and generals he was deposed and condemned to death. Taksin’s chief general, Chao Phya Chakri, who had for some time been the real ruler but was at the moment away on a campaign in Cambodia, was crowned King on his return in 1782 as Rama I. He chose Bangkok as his capital, and began to adorn it with palaces and temples on the model of Ayutthaya. Rama I was the first King of the dynasty which still reigns in Thailand today. His full title was Somdetj Phra Buddha Yot Fa Chulalok, Rama I. He reigned from 1782 to 1809.
During the first years after the fall of Ayutthaya the Thais made great efforts to restore their lost traditions. Following the accounts of survivors, the court ceremonial was re-established, and officials were ordered to follow the old laws. The re-codification of the laws was completed in 1805. 350 monks and laymen produced a new edition of the basic Buddhist rules and doctrines. The ancient Buddha figures were brought to Bangkok from the abandoned temples to embellish new monasteries, whose architecture closely followed older models.
Rama I’s son ascended the throne as Somdetj Phra Buddha Loes La Nabhalai, Rama II and reigned until 1824. He was a highly gifted monarch, and devoted himself to preserving the few remains of Thai literature that had survived the fall of Ayutthaya.
Under his son, Somdetj Phra Nang Klao, Rama III (1824-1851), new developments gradually took place, with less exclusive regard for the revival of tradition. Trade with China flourished, and Chinese merchants began to develop sugar plantations. Tin from the mines of the Malay peninsula became an important export.
But the most decisive innovation was the, at first hesitant, re-opening of the country to western trade. A group of influential nobles under the leadership of Prince Mongkut aimed at the extensive introduction of western ideas. After the death of Rama III, Prince Mongkut was crowned King as Somdetj Phra Chom Klao, Rama IV.
Before Mongkut succeeded to the throne on the death of his half-brother he had lived for 27 years in a Wat as a Buddhist monk. During this time he had learnt Latin and English, had familiarised himself with foreign customs, and had observed the cultural and political influence of Europe on the neighbouring states. He believed that Thailand could only maintain its sovereignty in the face of the colonial powers by adopting western methods. Accordingly, soon after his accession, he entered into diplomatic relations with the European powers and the U.S.A. In keeping with this, Thai trade, which had previously been subject to many restrictions, was much liberalised. A trade treaty was signed with Britain in 1855, and with France in 1856. Other states followed: Denmark, Portugal, Holland, Prussia (1862), Belgium, Italy, Sweden and Norway. During this period a currency was instituted, the first printing-press established and a government newspaper published. The King also supported Christian missionaries, whose services as teachers and doctors he appreciated. He had European teachers for his sons, and did all he could to spread western ideas. Finally, he promoted the codification of Thai law on western lines. Territorially, however, when France established a protectorate over Cambodia, he had to abandon his territories there with the exception of the provinces of Battambang and Siem Reap.