At the end of the 19th century, Siam was remade as a nation-state. The ‘nation’ constructed by this process was novel. The areas collected within the borders had very different histories, languages, religious cultures, and traditions. The Thai language seems to have been spoken in the lower Chao Phraya river system and down the upper peninsula, but in practice local dialects varied greatly. Over the prior century, the expansion of Bangkok’s political influence, the influx of war captives, and Chinese immigration had added to the social variety. The fragmentation of the administration gave scope for local difference.

The massive economic and social changes begun in the American era spilled into politics over the last quarter of the 20th century. After 1976, the senior bureaucracy, palace, and military still clung to the model of a passive rural society that accepted the hierarchical social and political order and that needed to be protected against both communism and capitalism. The generals and bureaucratic elite laid plans to engineer social harmony and guide ‘democracy’ from above. But economically and culturally, the country was rapidly becoming more urban than rural, dominated more by business than by bureaucracy, and more assertive than passive. The paternalist vision was swept away by the advance of industrialization, urbanization, globalization, and the growth of mass society.

Although the capital was physically destroyed in 1767, Ayutthaya represented traditions of trade and rule that were not easily erased. Over the next 15 years a new capital emerged further down the Chao Phraya River located at Thonburi-Bangkok, a site with better chaiyaphum for trade and defence. Members of the old elite dramatized Bangkok as a revival of Ayutthaya. But in fact much was very different. This era of war extended the Siamese armies’ influence further to the north, south, and east than ever before. Forced movements of people transformed the ethnic mix in the Chao Phraya plain. The great noble households that survived the crisis became the dominant force in the polity.

The name Thailand was invented in 1939. The country it described, formerly called Siam, had been defined by borders drawn in the 1890s and 1900s. Its capital, Bangkok, had been founded in 1782 in succession to an older city, Ayutthaya, destroyed 15 years earlier. Ayutthaya had been one of the great port cities of Asia, with trading links stretching from Persia to China and a political and economic hinterland focused on the basin of the Chao Phraya river system.

With the appearance of the Future Forward Party, and especially with youth protests in 2020, age became a factor in Thai politics as never before. Behind this was more than the perennial clash of hope and conservatism. Because of the rapid changes over the prior 70 years, successive generations had grown up in different worlds, shaping different mentalities.

The era of development incorporated more people more firmly into the national market economy. The era of national security brought more people more firmly under the direction of the nation-state. Armed with new funds and technologies, the nation-state extended its power deeper into society, and further into the villages and hills. Struggles to control and direct the nation-state now affected the lives and commanded the interest of larger numbers of the nation’s citizens.

After the Second World War, the US became a new foreign patron more intrusive than anything Siam had experienced in the colonial era. While Britain had focused on its colonies and had never taken more than peripheral interest in Siam, the US seized on Thailand as an ally and base for opposing the spread of communism in Asia. To build Thailand’s capability for this role, the US helped to revive and strengthen the military rule, which had faltered at the close of the Second World War, and supported a revival of the monarchy. To consolidate Thailand’s membership of the ‘free world’ camp in the Cold War, the US promoted ‘development’, meaning primarily economic growth through private capitalism. To achieve ‘national security’, US funding helped to push the mechanisms of the nation-state more deeply into society than before.

The nation-state was new. So too were its citizens, as a result of two sweeping social changes. Beginning in the early 19th century, the landscape and society of the lower Chao Phraya basin were transformed by a frontier movement of peasant colonization. Uniquely in Asia, new land was being opened up faster than the population was growing from the mid-19th century right through to the 1970s. As a result of political decisions in the late 19th century, this frontier society was characterized not by landlords but by peasant smallholders. Until urbanization accelerated in the last quarter of the 20th century, this peasant smallholder society represented four-fifths of the population and was the main driving force of the economy.

In the latter part of his reign, Chulalongkorn and his supporters repeatedly justified the creation of a strong state and its absolutist management on grounds of the need for Siam to progress and be a significant country in the world. This formulation marks the start of one of the two recurring visions in modern Thai politics. The same idea, adapted to changing international and local contexts, reappeared over the following decades. The Chulalongkorn era had also created the key vocabulary of this theme, particularly the notion of samakkhi, unity, and its highly masculine and militaristic imagery, exemplified by Chulalongkorn’s equestrian statue and Damrong’s account of Thai history as a series of wars.