After Ayutthaya was burned by the Burmese army in 1767, the Thai army   established Thonburi, a community of Bangkok as the new capital.  Bangkok   was instituted as the new capital in 1782 by king Chakri, also known by his   dynastic name Rama I.  After asking Chinese merchants to move to the   Sampeng area, Rama I used the vacated land to build the Temple of the Emerald   Buddha (Wat Phra Kaew).   Another thing he did was to give Bangkok a   royal name, one that happened to include the title Krung Thep ("City of   Angels"), which was what Ayutthaya had been called.
After being expelled from Thailand in 1688, foreigners started sprinkling   into Bangkok.  Initially, there were a few merchants and missionaries in   the 1830's, and by 1860 many European countries and North America had trade   treaties with Bangkok.
The King and I, a movie based on King   Mongkut, is still banned in   Thailand today since many feel it is not an accurate portrayal of him.    King Mongkut (1851-1868), and later on his son King Chulalongkorn (1868-1910)   is responsible for the modernization that has taken place in Thailand.    The city's first paved street was built under his rule and in 1863, his son   sustained it by building more city roads, constructing a rail line to go north   as well as adding a tram line.  
With the turn of the 20th century, Bangkok began growing even more, with   former rural market areas turning into residential areas.  In an effort   to promote growth and development in Thonburi, Memorial Bridge was constructed   in 1932 to connect it to Bangkok.  Other efforts at modernization   included filling in canals to make more land area and roadways.  
The Vietnam War really brought about growth in Thailand with all the money   that streamed in and improvements were made to existing problems, such as   widening the road to the Don Muang airport.   World War II and   Thailand's "alliance" with Japan caused problems particularly toward   the end of the war with Bangkok being bombed by the Allies.
Increased population and modernization from the 1960s on have caused some   problems in Bangkok.  The housing situation is deplorable as there are   over 8 million people in Bangkok and a direct result of the population and   modernization explosion is a problem with severe traffic congestion.    Some may feel that the loss of many cultural sections of Bangkok is a high   price to pay in the name of modernization, especially since these areas with   their markets and inhabitants have disappeared to make way for shopping centers.    Bangkok is now most other modern cities in the world.
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