"In the 1830s, canals were built east and west of Bangkok to serve as highways for trade and military movements. These canals drained areas of swamp which were immediately settled by people seeking rice land.
"This new frontier allowed peasant settlers to flee beyond the reach of labour controls and policing. For the most part, the government made no objection, while gradually increasing the range of taxes on production, commerce, and entertainments. But from mid-century, it became worried about 'banditry' in the rural areas, and over the following decades this worry expanded into an obsession. Some of the bandits were peasants who had suffered a bad harvest or other misfortune. Some were running opium, liquor, and gambling rackets. Some were professional cattle rustlers. Some were just nakleng, local toughs who defended their village against predators, including moneylenders and tax collectors. These bandits ambushed convoys carrying tax returns back to Bangkok, looted government granaries, and seized land. Some became instant folk heroes, celebrated in ballads for their defiance of authority. In some places, peasants copied the example of angyi to form associations for the same mix of self-protection and defiance of the law."