16 February – More than 100 million Indians cast their votes for 222 seats in the first phase of the general election. At least 21 people die in scattered violence.
21 February – The Hindu nationalist BJP is ousted from power in Uttar Pradesh State after a coalition ally withdrew its support. On 23 February, a bitter court battle restores the BJP-led government to power.
22 February – The second phase of general elections is held for 184 seats.
26 February – The BJP wins a vote of confidence in Uttar Pradesh.
28 February – In the third major phase of general elections, the electorate votes for 131 seats.
2 March – The counting of votes begins after elections marred by violence in which at least 150 were killed. The BJP and their allies emerge as the single largest political formation with 251 seats, the Indian National Congress and its allies winning 166 and the United Front 96.
3 March – Congress says it is willing to form a government with the United Front's support to stop the BJP from ruling.
14 March – The AIADMK agrees to support the BJP but says it will not join its planned government.
15 March – Sonia Gandhi says Congress does not have the support to stake a claim to rule. The AIADMK agrees to join a BJP-led government. The president invites Vajpayee to form a government and take the oath as prime minister on 19 March and gives him ten more days to prove his parliamentary majority.
19 March – Vajpayee takes office after assembling a diverse cabinet reflecting his 13-party coalition.
28 March – The BJP-led coalition wins a parliamentary confidence vote by 13 votes thanks to last-minute backing from the regional Telugu Desam Party.
14 April – The BJP unanimously elects senior leader Khushabhau Thakre as its new president. Thakre formally takes over in early May from Lal Krishna Advani, who is widely credited with crafting the political strategy that took the BJP from obscurity to power.
19 April – Jayaram Jayalalitha, leader of key coalition partner AIADMK, demands the removal of three ministers facing graft charges. The communications minister is sacked.
13 May – India carries out 2 more nuclear tests at Pokhran. The United States and Japan impose economic sanctions on India.
1 June – Finance Minister Yashwant Sinha presents a budget for 1998–99 (April–March) which sends stock markets lower. Under pressure from industry and markets, the government makes some embarrassing rollbacks on its budget proposals.
6 June – The UN Security Council votes unanimously to condemn India and Pakistan for their nuclear weapons tests.
9 June – Over 1,120 people are killed when a cyclone hits coastal areas of the western state of Gujarat.
20 July – Jayalalitha launches another salvo against the coalition government, giving it a two-day ultimatum to implement a Supreme Court ruling on supply of river water to her southern state of Tamil Nadu or face "disastrous consequences".
4 August – Guerrillas in Kashmir kill 19 people as cross-border firing by the Indian and Pakistani armies runs into its sixth day. On 5 August, at least 104 people are reported dead.
7 August – The AIADMK decides to continue its support after a water-sharing deal is struck between four southern provinces.
9 August – In Kashmir, separatist Ali Mohammad Dar, the self-styled deputy supreme commander of the banned Hizbul Mujahideen, is killed in a gunbattle with Indian police.
10 August – A further 19 people die as violence flares across the disputed region.
25 September – President K.R. Narayanan deals a blow to the Indian cabinet, urging it to review its recommendation to fire the government in the crime-plagued eastern state of Bihar.
18 October – Pakistan and India end their first peace talks in a year with agreement to meet again next February in New Delhi.
6 November – The first talks between India and Pakistan since 1992 over the disputed Siachen glacier end when Pakistan rejects an Indian proposal for a ceasefire.
26 November – A passenger train rams into another train in the northern Indian state of Punjab, killing at least 201 people.
29 November – The BJP pays a heavy price for its failure to halt a surge in the price of food items, especially onions, losing local elections to the main opposition Congress party in the key Hindi heartland states of Delhi and Rajasthan and failing to wrest control of the central state of Madhya Pradesh.
29 December - A major communal riot erupted in Surathkal near Mangalore, Karnataka. The unrest continued for about a week and 8 people were killed.