On January 8, India's lower house of parliament approved a bill that would grant residency and citizenship rights to undocumented non-Muslim immigrants, sparking protests in the country's northeast. The protests took place mainly in the state of Assam, where millions of people were accused of being foreigners and effectively stripped of their citizenship last year.

The controversial Citizenship (Amendment) Bill 2016, which still needs the approval of the upper house of parliament, seeks to amend the 1955 Citizenship Act to make Hindus, Sikhs, Buddhists, Jains, Parsis and Christians from three Muslim-majority countries - Bangladesh, Pakistan and Afghanistan - eligible for Indian citizenship. This would mean migrants belonging to these religious communities who entered India without the necessary documents prior to 2014 would not be imprisoned or deported and would gain permanent citizenship after six years of residency in India.

The government says the bill aims to provide succour to persons who have been persecuted in their homelands because of their religious identities and who have "nowhere else to go but India". The proposal assumes persons who identify as Muslim cannot be persecuted in Muslim-dominated countries, and therefore excludes all Muslim immigrants. Hence, members of the Ahmadiya and Shia communities of Pakistan, despite being persistently targeted by extremists, would not be able to seek refuge in India.

The bill has been widely criticised for attempting to make religion an eligibility criterion for Indian citizenship - an act that would fundamentally alter the secular character of India.

Ignoring minorities from non-Muslim states

Critics have questioned the reasons behind the government's decision to limit the scope of this bill to migrants from Muslim-majority neighbours of India. Some have argued that the fact that the proposal excludes thousands of undocumented immigrants from Sri Lanka, Nepal and most importantly Myanmar implies that the Indian government is not at all concerned about the persecution of minorities if they are not living in Muslim-majority countries.

Indeed, when members of Myanmar's Muslim Rohingya minority sought refuge in India after being persecuted in their home country for their religious and ethnic identity, the Indian government did not attempt to provide any legal protection for them. On the contrary, the members of the government perceived these desperate refugees as a threat to India and made attempts to force them out of the country.

In this context, the claim that this bill is a humanitarian gesture aiming to help people in need does not hold. So what is the Indian government's real motivation for supporting this bill?

Protecting India's 'Hindu identity'

The governing Hindu-nationalist Bharatiya Janata Party's (BJP) main strategist for the northeast, Himanta Biswa Sarma, recently exposed the real purpose of this bill: protecting India's so-called Hindu identity.

Before the citizenship bill was put to a vote in the lower house of parliament, Sarma, who is also the finance minister of the state of Assam, said, "If this Bill is not passed, then Hindus in Assam will become a minority in just next five years. That will be advantageous to those elements who want Assam to be another Kashmir and a part of the uncertain phase there."

And soon after the bill was passed, the minister argued that this decision may have prevented Muslims from taking control of Assam's 17 assembly seats and the Muslim leader of the All India United Democratic Front (AIUDF), Badruddin Ajmal, from becoming the chief minister.

By using the potential electoral success of Muslim Indian citizens, who have every right to contest and hold public positions, as a way to legitimise the citizenship bill, Sarma clearly demonstrated that the purpose of this bill is not to "help" anyone, but to protect and promote Hindu supremacy in India.

Prime Minister Narendra Modi has also previously admitted that the bill is tied to his party's desire to make India a Hindu nation that prioritises the rights of Hindus irrespective of their citizenship.

During a rally in Assam's Bengali-Hindu dominated region of Silchar, Modi said that the citizenship bill is an "atonement for the past mistakes of partition". Emphasising that he believes blood relations are more important than the "colour of passports", he promised the region's Bengali-speaking Hindus that he would make sure that they will be accepted and welcomed by "mother India" by passing this bill.

Alienating Assam's indigenous population

Today, Assam is at the centre of protests about the proposed amendment to India's citizenship bill and this public anger has historical roots.

During Bangladesh's bloody struggle for liberation from Pakistan in the early 1970s, many Bengalis moved to Assam. Over the years, their increasing numbers stirred anxieties among the indigenous Assamese people about the preservation of their distinct culture and ownership of land. As a result, between 1979 and 1985, an "anti-foreigner" agitation - dubbed the "Assam movement", targeting the Bengali immigrants - erupted in the state.

To end the violence, India's central government signed the Assam accord with the leaders of the Assam movement in 1985. The accord specified that only people who could prove that either they or their parents had entered or lived in India prior to March 1971 can assume Indian citizenship and legally reside in the state of Assam.

Last year, a new National Register of Citizens (NRC) was prepared in the state to distinguish Indian citizens from undocumented immigrants according to the rules set by the 1985 accord. This list included only 28.9 million of the 32.9 million people residing in the state, rendering nearly four million people stateless.

The decision to denationalise millions of people was widely supported by Assam's indigenous population, which still fears their culture may be decimated by the influx of "foreigners" and widely criticised by India's Bengali communities and international observers. The Assamese's main fear is that Bangla-speaking people from neighbouring Bangladesh, irrespective of their religion, would come to dominate Assam. Hindu and Muslim Assamese are united on this viewpoint and they all want undocumented immigrants to be kicked out of the state.

However, with this new citizenship bill, the BJP government is trying to convince Assamese Hindus that their loyalty should lie not with the indigenous Muslim communities of their state - who speak their language - but with Bengali Hindus. For now, the majority of Assamese Hindus seem not convinced by Hindu nationalist arguments.

The Assam Gana Parishad (AGP), the successor of the Assam movement, has already severed ties with the BJP and expressed its displeasure over the move. The AGP and its allies see in this move an attempt by the BJP to lure as many Hindus from Bangladesh as possible to this region, which, they think, would make it Bengali-dominated and eclipse the local cultures.

Another step towards Hinduisation of India

The citizenship bill needs to be seen as a part of the BJP's larger ideological and political agenda to transform India into a "Hindu homeland". The governing party believes India belongs to Hindus and everyone else are invaders, or at best latecomers, who should expect nothing more than a guest status.

The BJP is clearly using this bill to send a message to the Hindus in other parts of India that under their rule, "Hindus will always come first".

From the very beginning, the BJP viewed the NRC as way to rid the country of Muslim "foreigners". Using this citizenship bill, the governing party is trying to make sure no Hindus are harmed by the NRC and their quest to expel Muslims from India can continue without complications.

If this bill gets the approval of the upper house in the coming days, it will not only cause division and conflict in the northeast of India but will significantly contribute to the ongoing Hinduisation of India.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial stance.