Of the many changes Thailand has undergone since Bhumibol came to the throne, the growth in the nation's economy is among the most spectacular. Largely agrarian when he came to power, Thailand has since become an industrial and service-sector giant and is the second largest economy in Southeast Asia after Indonesia.
It remains one of the world's top rice producers and has become one of the most popular tourist destinations. It is also a regional manufacturing hub for the motor vehicle industry and hi-tech electronics.
As wealth has poured into the country, living standards have risen significantly, upsetting the social balance in a country that leading scholars dubbed a "network monarchy": an extensive network of royal patronage that extends outward from the palace into the rest of society.
The largely rural and populous northeast of the country, a region in which Bhumibol worked enthusiastically to promote agricultural and social development, has experienced rising prosperity, creating a growing middle class.
The northeast was also a bastion of support for Thaksin, whose populist policies helped generate a political movement that unsettled the established elites. Since Thaksin was toppled in 2006, Thailand has been riven by political instability, as the country divided into political groupings that drew their support from a complex network of associations: on one side, the generally pro-Thaksin red shirts whose support comes mainly from rural communities in the north and east; on the other, the urban and middle class elites, who largely favour a less populist, more paternalistic form of governance.
Despite sometimes violent factionalism, all sides claim allegiance to the King. His intense popularity allowed for widespread celebrations of his 80th birthday in 2007, when millions wore yellow, a color associated with the King.