FOLLOWING the crooked finger of the Brahmaputra river east and north towards its Tibetan origin, Assam looks like no other place in India. Its lush riverine lands have attracted incomers since ancient times. The result is a medley of peoples of varied languages, dress, cuisines—and political interests.
Yet in the current state election the prize will go either to the incumbent Congress party or to the Bharatiya Janata Party (BJP) of the prime minister, Narendra Modi. For the first time, it is making inroads into India’s north-east, as the spectre of illegal immigration from Bangladesh threatens to realign politics in the BJP’s favour. The third parties that represent specific Assamese groups have been shunted into supporting roles, setting the stage for a battle royal between India’s two chief national parties. Should the BJP win in Assam, which with 33m people is the biggest of the north-east’s seven states, the party will be able to claim a brand that now works in every corner of the country.

Mr Modi’s familiar emphasis on the economy goes down well in Assam. But turning the state’s complicated human terrain to the advantage of his party, which has its roots in the Hindi-speaking north and west, requires attention to local detail. The Assamese are anxious to preserve their cultural identity, a mix that combines the easternmost Indo-European stock with ethnic groups of Tibeto-Burman and Tai origin (ie, related to present-day groups in Thailand and Laos), clusters of endemic tribes, and also the “tea tribes” brought by the British from east-central India to work plantations. The BJP’s standard appeal to Hindu-first Indian nationalism never found a wide audience in a hybrid state with occasionally secessionist tendencies.

But Assam also happens to be 34% Muslim, more than any state bar Jammu and Kashmir. Over the past quarter-century the proportion of Muslims has grown rapidly, even as the proportion of Assamese speakers has dipped below 50%. Here the BJP’s strategist, Amit Shah, scented opportunity, claiming in November that the state government was conspiring with a smaller Muslim party, the All India United Democratic Front, to let Bangladeshis pour over the border and change the demographics in the party’s favour. Bangladesh, Mr Modi has also claimed, sounding like an Indian Donald Trump, was sending intruders over the border; his government, given power in the state, would round them up and kick them out. Bengali-speaking Muslims feel threatened, even though many live in communities that have been in Assam for generations, if not centuries. Many have decamped from Congress, their usual party, to the Muslim third party, because it is devoted to their protection.
Though the greatest number of the state’s Bengali-speaking Muslims are descendants of immigrants who arrived under British supervision in the first decades of the 20th century, no one really knows how many have entered Assam illegally since Bangladesh was founded in 1971. Supposedly to determine the number, a National Register of Citizens is being compiled—for Assam only.
Publication of its findings has been postponed several times before the election and will not happen now until after the vote is declared on May 19th. The chances are that relatively few Bangladeshis will be decreed to be in Assam and due for deportation. After all, why would great numbers of poor Bangladeshis want to move to Assam in the first place? Its living standards have improved greatly under the government of the chief minister, Tarun Gogoi, yet they still lag far behind those of Bangladesh. Still, that truth sits uncomfortably with those keen to work up communal divisions for electoral gain.