1830-68 The period which saw the beginnings of significant Western economic and cultural impact on Thailand in the reigns of King Rama III and King Rama IV, Mongkut.

1868-1910 The period during which King Rama V, Chulalongkorn, consolidated the absolute monarchy in response to the economic and political pressures generated by Thailand's increasing participation in the European colonial systems.

1910-32 The period of growing tension between the traditional aristocracy and the newly recruited non-aristocratic bureaucracy, which ultimately led to the revolutionary overthrow of the absolute monarchy in 1932.

1932-57 The period of élite conflict, largely under the political domination of Field Marshal Phibun Songkhram, who distrusted the aristocracy and who unsuccessfully attempted to transfer control of the economy from the Chinese to the ethnic Thai bureaucracy through the imposition of state capitalism.

1957-73 The period of élite consolidation and reconciliation under Field Marshal Sarit Thanarat and Field Marshal Thanom Kittikachorn, who forged political and economic alliances between the bureaucracy, the aristocracy, and large Chinese commercial interests, which established a powerful alliance of interests in the modern Thai establishment.

1973 to present The contemporary period, characterised by the growth of an urban professional and middle class in conflict and competition with the aristocratic-bureaucratic-commercial establishment.