Israeli Prime Minister Ariel Sharon, who was generally popular among Israelis but deeply disliked in much of the Arab world, was left incapacitated after suffering a massive stroke on January 4. A former army general, Sharon was tirelessly committed to preserving Israeli security, and by the end of his career advocated a pull-out from the Israeli settlements in the Gaza Strip and West Bank that he had once championed. Sharon was succeeded by Ehud Olmert, a member of the centrist Kadima party Sharon founded shortly before his stroke. At year's end, Sharon remained in a coma, and was not expected to recover.

Over the objections of Western nations, Iran removed United Nations seals from its uranium enrichment plant at Natanz on January 10. Research into making nuclear fuel was resumed the next month. Although Iran's president, Mahmoud Ahmadinejad, insisted the research was part of a peaceful energy program, it was widely believed that Ahmadinejad, who has threatened to wipe neighboring Israel "off the map," was actively seeking a nuclear weapon. Iran later ignored a July 31 U.N. Security Council resolution that gave the country one month to suspend uranium enrichment or face economic and diplomatic sanctions. As the year came to a close, an agreement on the matter still had not been reached.

The Danish and Norwegian embassies in Damascus were set ablaze on February 5 amid continuing controversy over a Danish newspaper's September 2005 publication of cartoons depicting the prophet Mohammad. Images of Mohammad are forbidden under Islamic tradition. Muslims around the world denounced the cartoons as anti-Islam and began a series of violent and non-violent protests against their publication. Meanwhile, supporters argued that the cartoons were a legitimate part of the debate over Islamic self-censorship and deplored the fact that journalists feared reprisals for criticizing the religion. The next day, the Danish embassy in Beirut was also torched, as protests continued throughout the month. An Iranian newspaper later responded by announcing a competition for the best Holocaust-themed cartoon to "test the boundaries of free speech."

As of April 2006, a record 13 female heads of state were in power around the world. These included Ellen Johnson Sirleaf, who took office in January as Liberia's president, becoming Africa's first female head of state; Michelle Bachelet, inaugurated on March 11 as the first female president of Chile; and Portia Simpson Miller, who became the first female prime minister of Jamaica on March 30.

Zacarias Moussaoui, a French citizen of Moroccan descent, was sentenced to life in prison in a U.S. federal court on May 3, after pleading guilty to charges of terrorism conspiracy related to the September 11, 2001 attacks. Although Moussaoui was already in a U.S. prison on September 11, authorities believe that lies he told investigators prevented them from uncovering the al-Qaida plot. During the trial, Moussaoui voiced his willingness to kill Americans "any time, anywhere." By year's end, he had begun serving his sentence at the federal Supermax prison in Florence, Colorado, known as the "Alcatraz of the Rockies." On May 23, Osama bin Laden released a tape claiming that Moussaoui had no role in the September 11 attacks.

Game of Shadows, a book by Mark Fainaru-Wada and Lance Williams chronicling baseball star Barry Bonds' alleged use of performance-enhancing drugs, was released on March 23. The book also detailed the authors' investigation into Victor Conte and his BALCO sports nutrition center, a steroid and performance-enhancing drug supplier, and pointed the finger at other high-profile athletes, including baseball player Jason Giambi and track stars Marion Jones and Tim Montgomery. Information revealed in the book led to an independent investigation by Major League Baseball into drug use within the sport. On May 28, Bonds passed Babe Ruth on the career home-run list after hitting his 715th homer, which landed him second only to Hank Aaron. As the year ended, Bonds had not been charged with a crime, but was under investigation for lying under oath to a grand jury.

In late May, Montenegro voted to secede from its union with Serbia, breaking up what remained of the former Yugoslavia. An independent Montenegro fought on the winning side in World War I, but was lumped with other Balkan states into Yugoslavia at the end of the conflict. In 1991, Slovenia, Croatia and Bosnia all fought to break ties with Serbia, while Macedonia seceded peacefully. As 2006 came to an end, the Albanian majority in Kosovo, which was wracked by violence in the early 1990s, also made plans to secede from Serbia. Meanwhile, in March, Serb leader Slobodan Milosevic, the former president of Yugoslavia who spearheaded his country's war with Bosnia, was found dead of heart failure in his prison cell in The Hague, where he was on trial for war crimes.

Also in late May, former U.S. Vice President Al Gore released An Inconvenient Truth, a documentary film chronicling his campaign to bring attention to the problems of climate change and global warming, issues that had been largely ignored by the American public. The film, which later won the Academy Award for best documentary, became one of the most successful documentaries ever produced, spurring renewed interest in preventing climate change both in the United States and around the world.

On May 25, one of the biggest corporate scandals in U.S. history came to a close when former Enron executives Kenneth Lay and Jeffrey Skilling were convicted of a total of 29 counts of conspiracy, securities fraud and insider trading. Prosecutor Sean Berkowitz later said of the trial, "The jury sent an unmistakable message: You can't lie to shareholders. No matter how rich and powerful, you must play by the rules." Lay died on July 5, before he could be sentenced. Skilling was sentenced to more than 24 years in prison, and fined $45 million.

Abu Musab al-Zarqawi, the Jordanian-born insurgent leader behind hundreds of bombings, kidnappings and murders in Iraq, was killed on June 8 after a U.S. air strike on a house near the city of Baqubah. Sheik Abdul Rahman, Zarqawi's spiritual advisor, was also killed. Zarqawi, the leader of al-Qaida in Iraq, was a high-profile U.S. target for his role in violence he said was aimed at ousting foreign forces from Iraq and stirring up conflict between Iraq's Shiite Muslim majority and members of his Sunni Muslim sect. Despite his death, violent turmoil in Iraq continued. The United Nations estimated that more than 34,000 Iraqi civilians were killed in 2006, along with more than 800 U.S. soldiers. By the end of the year, more than 3,000 U.S. soldiers had been killed since the war began, with another 22,000 wounded. In addition, nearly 100 died in Afghanistan in 2006, bringing that total to more than 350 since 2001. In November, former Iraqi dictator Saddam Hussein was found guilty of crimes against humanity and sentenced to death by hanging. He was executed December 30, 2006, after an unsuccessful appeal.

Warren Buffett, the world's second richest man, announced on June 23 that he would give away the bulk of his fortune—10 million Berkshire Hathaway shares, worth more than $30 billion—to charity. The lion's share went to the Bill and Melinda Gates Foundation, run in part by the world's richest man, Microsoft founder Bill Gates, and dedicated to eliminating disease and promoting education, especially in developing nations. When completed, Buffett's donation will be the largest charitable gift in U.S. history.

In late July, Cuban dictator Fidel Castro, the world's longest serving political leader, temporarily ceded power to his brother Raul, after announcing that he was suffering from an unspecified intestinal ailment. At year end, Raul Castro was still ruling the nation, and Fidel remained seriously ill, though the Cuban government still had not confirmed the nature of his illness. Most observers predicted that the controversial communist revolutionary would never return to power.

On August 10, a plot against multiple U.S.-bound airliners was thwarted by British and Pakistani authorities with the arrest of 24 alleged conspirators. The suspects had been planning to blow up as many as 10 passenger jets over the Atlantic Ocean by mixing a cocktail of liquid explosives smuggled aboard in carry-on luggage. British authorities had been watching the group since late 2005 and decided to move in when it appeared the attacks were imminent. In the United States, the terrorism threat level was raised to "red," marking the first time the highest level alert was used. U.S. Homeland Security Secretary Michael Chertoff said the plot, "was sophisticated, it had a lot of members and it was international in scope." News of the plot prompted the issuing of tighter flight restrictions, including a ban on carrying large amounts of liquids or gels aboard passenger planes.

Russian mathematician Grigory Perelman refused to accept the Fields Medal, the highest honor in math, on August 22. Perelman was given the award for solving the 100-year-old Poincare conjecture, widely believed to be one of the toughest problems in math. Perelman declined to explain his decision, but it was speculated that the math genius, known to be reclusive and disdainful of self-promotion, simply believes the discovery to be more important than who discovered it. Perelman may also turn down the $1 million prize he will likely be offered by the Clay Mathematics Institute if his proof remains unchallenged for the next two years.

Leading astronomers agreed on August 24 to demote Pluto in status from a planet to a dwarf planet, of which there are more than 40 in the Earth's solar system. Pluto was discovered and given planet status in 1930. Planets are now defined as objects that orbit the Sun, have become round due to the force of their own gravity, and dominate the neighborhood around their orbit. Pluto did not satisfy this last caveat.

Steve Irwin, the popular naturalist and television personality known as the "Crocodile Hunter," died on September 4, 2006, immediately after being stung by a stingray while shooting a television show off the northern coast of Australia. Stingrays, named for the venom-coated barb at the end of their tails, generally sting only in self-defense and rarely attack humans, and Irwin's death was the first such fatality in Australia in more than 60 years. Irwin was known to fans as an enthusiastic and passionate wildlife lover and was credited with encouraging the conservation of previously feared or disliked animals, such as crocodiles, snakes and other reptiles.

On October 2, Charles Carl Roberts IV shot 10 girls between the ages of 6 and 13 in an Amish schoolhouse in Nickel Mines, Pennsylvania, and then killed himself. Three of the girls died at the scene and two more died afterward. It was later revealed that the psychologically disturbed Roberts, a milk-truck driver, had molested two young female family members some 20 years earlier and that he'd told his wife he was tormented by visions of committing similar crimes. The murders hit the small, close-knit Amish community, where residents live a simple life without modern conveniences like electricity, extremely hard. Still, the devoutly religious Amish were quick to forgive the shooter, even urging others to pray for his family. The school was demolished in October.

Catherine Jeffords Shorie was named head of the Episcopal Church on November 4, becoming the first female leader in the church's more than 400-year history. Shorie, a wife, mother and former oceanographer, had been a priest just 12 years when she was elected to lead the church's 2.4 million congregants. A supporter of gay marriage and the ordaining of gay priests, Shorie said that she hoped the church would regain an "outward focus over internal issues" and become "a blessing to this world" instead of a "source of division" during her tenure.

On November 8, U.S. Secretary of Defense Donald Rumsfeld stepped down, one day after mid-term elections led to Republican loss of control in the House of Representatives and Senate, largely due to Americans' displeasure over the war in Iraq. Rumsfeld was replaced by Robert Gates. In December, the Iraq Study Group, appointed by the U.S. Congress, released a report recommending that the United States train Iraqi troops to take the place of American soldiers, though it did not give a specific timeframe for a U.S. withdrawal. As 2006 came to a close, the president and Congress had yet to agree on a change of course for the Iraq war.

Veteran rockers the Rolling Stones topped the list of the year's highest grossing concert tours. Their "Bigger Bang" tour, which kicked off in September 2005, pulled in an estimated $138.5 million in 2006 and became the top-grossing tour of all time. The top five also included familiar faces Barbra Streisand, Madonna and country duo Faith Hill and Tim McGraw. Overall, concert ticket sales in North America alone are estimated to have topped $3.5 billion.

General Augusto Pinochet, the notorious dictator who ruled Chile from 1973 to 1990, died on December 10, one week after suffering a heart attack. More than 3,000 Chilean political prisoners were killed under his brutal regime, and thousands of others were tortured or forced into exile. Although Pinochet was credited with bringing economic stability to Chile, he lost a popular vote in 1988 and reluctantly relinquished power. To the great frustration of his victims, he avoided standing trial for his crimes because of ill health. In a statement on his 91st birthday, Pinochet said, "...I take responsibility for everything that was done, which had no other goal than making Chile greater and avoiding its disintegration." In Chile, news of Pinochet's death was greeted by both celebration and sadness.

On December 25, American singer, songwriter and "godfather of soul" James Brown died of congestive heart failure at age 73. Brown's influence was felt across R&B and soul; he is also said to have all but invented funk and laid the groundwork for pop, rap and hip-hop. A winner of multiple Grammy Awards, Brown was inducted into the Rock and Roll Hall of Fame in 1986. Never one to mince words, he once said of himself, "Disco is James Brown, hip-hop is James Brown, rap is James Brown...you hear all the rappers? Ninety percent of their music is me." Though he had experienced problems with drugs and several times run afoul of the law, he remained a beloved music icon at the time of his death.

Former U.S. President Gerald Ford died on December 26 at age 93. After serving 20 years in Congress, Ford was appointed vice president by President Richard Nixon in 1973 following the resignation of Spiro Agnew. He assumed the presidency after Nixon stepped down in the wake of the Watergate scandal, becoming the only person to hold both offices without being elected to either. Ford is perhaps best known for ending U.S. involvement in Vietnam and pardoning Nixon, a much-criticized move at the time. Still, Ford was highly regarded in Washington, and was remembered as an extremely hard-working, fair-minded and honorable man, who restored America's hope and confidence and helped the nation to move past the divisiveness of the Watergate era.