Wikipedia reports that:
According to The New York Times, "he [Saddam] murdered as many as a million of his people, many with poison gas. He tortured, maimed and imprisoned countless more. His unprovoked invasion of Iran is estimated to have left another million people dead. His seizure of Kuwait threw the Middle East into crisis. More insidious, arguably, was the psychological damage he inflicted on his own land. Hussein created a nation of informants — friends on friends, circles within circles — making an entire population complicit in his rule". Other estimates as to the number of Iraqis killed by Saddam's regime vary from roughly a quarter to half a million, including 50,000 to 182,000 Kurds and 25,000 to 280,000 killed during the repression of the 1991 rebellion.Estimates for the number of dead in the Iran-Iraq war range upwards from 300,000.About.com reports 'Top 5 Crimes of Saddam Hussein', which include:
...it is estimated that up to 182,000 were killed during the Anfal campaign. Many people consider the Anfal campaign an attempt at genocide.
... As early as April 1987, the Iraqis used chemical weapons to remove Kurds from their villages in northern Iraq during the Anfal campaign. It is estimated that chemical weapons were used on approximately 40 Kurdish villages, with the largest of these attacks occurring on March 16, 1988 against the Kurdish town of Halabja.
Beginning in the morning on March 16, 1988 and continuing all night, the Iraqis rained down volley after volley of bombs filled with a deadly mixture of mustard gas and nerve agents on Halabja. Immediate effects of the chemicals included blindness, vomiting, blisters, convulsions, and asphyxiation. Approximately 5,000 women, men, and children died within days of the attacks. Long-term effects included permanent blindness, cancer, and birth defects. An estimated 10,000 lived, but live daily with the disfigurement and sicknesses from the chemical weapons.
At the end of the Persian Gulf War in 1991, southern Shiites and northern Kurds rebelled against Hussein's regime. In retaliation, Iraq brutally suppressed the uprising, killing thousands of Shiites in southern Iraq.
As supposed punishment for supporting the Shiite rebellion in 1991, Saddam Hussein's regime killed thousands of Marsh Arabs, bulldozed their villages, and systematically ruined their way of life.
Stanford University reports:
Along with other human rights organizations, The Documental Centre for Human Rights in Iraq has compiled documentation on over 600,000 civilian executions in Iraq. Human Rights Watch reports that in one operation alone, the Anfal, Saddam killed 100,000 Kurdish Iraqis. Another 500,000 are estimated to have died in Saddam's needless war with Iran. Coldly taken as a daily average for the 24 years of Saddam's reign, these numbers give us a horrifying picture of between 70 and 125 civilian deaths per day for every one of Saddam's 8,000-odd days in power"
The Iraq Foundation reports:
DOING the arithmetic is an imprecise venture. The largest number of deaths attributable to Mr. Hussein's regime resulted from the war between Iraq and Iran between 1980 and 1988, which was launched by Mr. Hussein. Iraq says its own toll was 500,000, and Iran's reckoning ranges upward of 300,000. Then there are the casualties in the wake of Iraq's 1990 occupation of Kuwait. Iraq's official toll from American bombing in that war is 100,000 — surely a gross exaggeration — but nobody contests that thousands of Iraqi soldiers and civilians were killed in the American campaign to oust Mr. Hussein's forces from Kuwait. In addition, 1,000 Kuwaitis died during the fighting and occupation in their country.
Casualties from Iraq's gulag are harder to estimate. Accounts collected by Western human rights groups from Iraqi émigrés and defectors have suggested that the number of those who have "disappeared" into the hands of the secret police, never to be heard from again, could be 200,000. As long as Mr. Hussein remains in power, figures like these will be uncheckable, but the huge toll is palpable nonetheless.
Scaruffi has a handy table listing The worst genocides of the 20th and 21st Centuries:
Saddam Hussein appears at number 13 on the list after Mao's Communist regime in China (49-78 million), Hitler's Nazi Germany (12 million), Leopold II massacre in The Belgium Congo (8 million), Stalin's Communist regime in Russia 9& million), Japanese Emperor Tojo's World War 2 massacres (5 million), The Ottoman Empire's massacres of Armenians, Assyrians and Greeks (2 million), Pol Pot's Cambodian regime (1.7 million), Kil Il Sung's North Korean regime's purges and concentration camps (1.6 million), Menghistu's Ethiopian regime (1.5 million), The Biafran killings (1 million), Leonid Brezhnev's Soviet regime's massacres in Afghanistan (900,000) and the Rwandan genocide of the 1990s (800, 000. The figure attributed to Saddam Hussein is 600,000.
So we have, excluding those victims of war, estimates of between 250,000 and 600,000 people killed by Saddam Hussein's regime. We have an agreed range. Well not totally agreed because @The_Mitch92 claims that only 5,000 were killed. Of course @The_Mitch92 has an agenda, he's claimed that