Nitish first came to limelight after winning the Bihar Assembly election as an independent candidate in 1985. Since then, he marched forward in his political career. A couple of years later, he was made the president of the Yuva Lok Dal and was then served as the secretary general of the political front Janta Dal in the state of Bihar. In 1989, general elections, he became an MP from Lok Sabha. He was re-elected again in 1991, and 1998 and served as an MP till 2004.
In Atalji’s cabinet, he served as Minister of Agriculture, Minister of Surface Transport and Minister of Railways. During his tenure as Railway Minister, he made revolutionary changes in Railways by introducing E-ticket and Tatkal services.
Nitish along with BJP fought together for the 2005 Bihar assembly election and won by a huge margin. Thus, he was appointed as the Chief Minister of Bihar. He won again in 2010 and 2015 Bihar elections and is still serving as a Chief Minister of Bihar. The grand alliance with whom he form the government in Bihar after 2015 elections dissolved in 2017 but he formed an alliance with BJP immediately and retained his post of CM of Bihar.
Though he joined politics in 1985 but was actively participating in protesting against governments and during emergency imposed by Indira Gandhi, he joined the movement led by the veteran Jai Prakash Narayan from 1974 to 1977. He was a close associate of Satyendra Narayan Sinha.