The vote is a key step towards culmination of the peace process that started with the signing of a November 2006 deal following which the Maoist rebels ended their decade-long armed struggle and joined the political mainstream.
After two years of political hassle and a series of negotiations, the major political parties, including the Maoists have agreed to hold the twice-postponed Constituent Assembly polls with the common agenda to establish a federal democratic republic.
The fate of King Gyanendra and his throne has been among the most contentious issues in the country, with the fiercely Republican-minded Maoists pushing the mainstream parties to agree to abolish the monarchy subject to ratification by the constituent assembly.
The embattled King, who was stripped off most of his powers after street protests forced him to give up his 14-month absolute rule, in a message on Wednesday asked the people "exercise their democratic right" in the election.
The election is also been seen as critical test for the Maoists who have returned to political mainstream after a decade of warfare.
Before the polls, mainstream political parties accused the former rebels of intimidating voters and preventing them from campaigning.
Image: A Nepalese man casts his ballot in Kathmandu on Thursday.
Photograph: Pedro Ugarte/AFP/Getty Images
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