Janata Dal was formed in Bangalore by the merger of the Janata Party with smaller opposition parties in 1988.In May 1996, H.D. Deve Gowda, now leader of Janata Dal (Secular), became Prime Minister of India as part of a coailition (called United Front) government.
Janata Dal split in 1999 when some leaders left to ally with the BJP-led National Democratic Alliance and form the Janata Dal (United) party. That party was led by George Fernandes while Deve Gowda emerged as the leader of the Janata Dal (Secular). Even though the premise for the split was its opposition to allying with the National Democratic Alliance, Deve Gowda stayed equally away from the Congress from the outset. Gowda wanted the party to remain equi-distant from both the Bharatiya Janata Party and the Congress. In spite of its difference with the Janata Dal(United) on the issue of support to National Democratic Alliance, the two parties were united in their anti-Congress stance. Gowda wanted the parties to merge in future but the Janata Dal(United) was not keen to ally with Gowda.
H.D. Deve Gowda is still the leader of the party and is a member of Lok Sabha for the Hassan district in Karnataka. His party is the third-largest in the Karnataka state legislature and for a time governed in a coalition with the Congress party (INC), the first coalition government in Karnataka. There was much controversy over the JD(S) allying with the INC in Bangalore as the INC formerly had an outright majority and was diminished to second place with the BJP having a plurality. The BJP saw the rise in seats for both BJP and JD(S) as being a sign that the voters did not want an INC state government and were very upset when the kingmaker JD(S) party decided to ally with the INC to gain a majority. However, the JD(S) considered INC to be the lesser of the two evils on account of its erstwhile secular and centre-left credentials.
Janata Dal had split once again between its two leaders in 2005 as JDS(Siddaramaiah) group (AIPJD) and JD(S) (Deve Gowda) group. This was due to the fact that Deve Gowda did not give any regard for the backward Kuruba community, which Siddaramaiah belonged to. Also, he was being marginalised in the party as Gowda was only giving preference to his sons H.D. Revanna and H.D. Kumaraswamy. Later, Siddaramaiah and his supporters such as former union minister C.M Ibrahim quit the party and joined the Congress. Siddaramaiah contested the Chamundeswari assembly by-poll as a Congress candidate and trounced the joint candidate of Deve Gowda group and BJP.
The ideologically dedicated section of the JD(S) led by veteran socialist leaders such as Surendra Mohan, M.P. Veerendre Kumar, Mrinal Gore and P.G.R. Sindhia has expelled Deve Gowda and his supporters in 2006 for aligning with the 'communal' BJP and betraying the JD(S)'s commitment towards secular ideology. But Gowda suspended these rebels from the party and these rebels formed the breakaway Janata Dal (Left). Later, P.G.R. Sindhia quit the party joined the BSP and became its national general secretary.
JD(S) national general secretary and son of former Karnataka CM J.H. Patel, Mahima Patel, quit the party in October 2007 following the JD(S) refusal to transfer power to BJP and formed his own party, Suvarna Yuga, in December 2007.
Exasperated with the party leadership for having put them in a fix by denying power to the BJP, veteran socialist leader M.P. Prakash, quit the JD(S) in December 2007 along with 12 former MLAs such as former ministers Amaregowda Byyapura, Suryanarayana Reddy, H.S. Mahadeva Prasad etc. They joined the Congress in March 2008.
Former minister G.T. Devegowda, who hails from Mysore, joined the BJP in December 2007, dealing yet another blow to JD(S).