Yingluck Shinawatra is the first female prime minister of Thailand, and the fifth person to hold that position since her older brother, Thaksin, was deposed in 2006.
Thailand has been beset by political division ever since Mr Thaksin was ousted.
Both his supporters and enemies have vied for power in parliament and on the streets.
Last year, red-shirted demonstrators, the majority of whom were Thaksin allies, laid siege to parts Bangkok.
Both parties in this election campaigned on the need for unity after a period marked by bloodshed and bitter recrimination.
The outgoing Prime Minister, Abhisit Vejjajiva, in the latter stages of his campaign focused on a warning – a vote for Yingluck was really a vote for Thaksin, and that would lead to the exiled leader’s pardon and homecoming.
However, these tactics appear to have backfired.
Yingluck Shinawatra’s must now reassure those who doubt her abilities and question whether she is more than a mere proxy for Mr Thaksin’s political ambitions.
She campaigned on the family name and has promised to revive her brother’s populist policies.
However, now has to show she is able to lead in her own right and step out of her brother’s shadow.
Her party has floated the idea of an amnesty to promote reconciliation in the country. But critics fear the idea is a ruse to usher her brother back to power.
Both siblings deny that, but Mr Thaksin has made no secret of the fact that he would like to return to Thailand “when the time is right”.
This election was about putting the country’s fate back in the hands of its people. But democracy in Thailand has too often been derailed.
The question then is whether this decisive victory for another member of the Shinawatra family will mark a new start, a chance to leave the vitriol and violence behind.
Or could Thailand’s fragile democracy be challenged once again?