The resignation of Thai Prime Minister Thaksin Shinawatra Tuesday ended the tenure of the longest-serving civilian prime minister in modern Thai history. It was a development that few would have predicted one year ago, following his landslide re-election.

Thaksin Shinawatra announced, in a subdued tone, Tuesday that he was resigning as prime minister, saying the time had come for unity and national reconciliation.

The mood was quite different 14 months ago when Mr. Thaksin made history as the first prime minister in modern Thai history to complete his term in office and win re-election.

During a campaign interview then, Mr. Thaksin, one of Thailand's richest men, explained what made him so popular among the poor, rural Thais who make up 70 percent of the population.

"I want to eradicate poverty. Poverty is very important," he said. "We have to help them [poor people]."

Thaksin Shinawatra was born on July 26, 1949, into a family of silk merchants originally from southern China.

He attended school in his native Chang Mai province, in northern Thailand, and graduated from Thailand's Royal Police Academy in 1973. Five years later he received a doctorate in criminal justice from Sam Houston University in the United States.

In the mid-1980s, he founded an electronic paging and mobile telephone company that grew into a multi-billion dollar telecommunications empire.

He entered politics only in the mid-1990s, serving in a coalition government as foreign minister and deputy prime minister before founding his own party in 1998, the Thai Rak Thai, or Thais Love Thais, party.

His party won the 2001 elections by a landslide. After surviving a legal challenge to his victory, Thaksin implemented his populist policies: subsidized public health programs, low-cost loans for rural poor, and village-based micro-industries.

He also lowered interest rates, leading to a consumer-based economic boom, and paid off billions of dollars worth of international loans left over from the 1997 financial crisis.

But economists said his fiscal policies were not sustainable. And human rights groups accused his government of heavy-handed tactics in campaigns to suppress the illegal drug trade and a separatist insurgency in the Muslim-dominated south.

Moreover, media advocates complained that he muzzled criticism in the press. And civic groups accused him of undermining checks-and-balances in Thailand's fledgling democracy while favoring business cronies and political allies with lucrative government contracts.

The author of a book on the Thaksin era, Chris Baker, says Mr. Thaksin was an innovative force in Thai politics.

"He had some very good policies indeed, both his social policies and his economic policies," he said. "I think it is a pity that a man who wanted to control the country cannot control himself or his family or his cronies."

Mr. Thaskin resigned after months of protests that intensified after his family's tax free-sale of nearly two billion dollars of stocks in the company he founded.

In resigning, Mr. Thaksin said he would stay on as head of his party and he left open the possibility of rejoining the political fray after some time outside Thai politics.

Baker says whatever his future, Thaksin Shinawatra has changed Thai politics.

"He has raised the expectation of the mass of the people in this society who in the past have not expected very much from politics, from government," he added.

Baker says that as a result, millions of Thais, particularly in poor, rural areas, have seen the value of their vote and its importance in a democratic system.