(CNN) -- Here's a look at what you need to know about Haiti, the poorest country in the Western Hemisphere. Haiti makes up the western one-third of the island of Hispaniola in the Caribbean. The eastern two-thirds of the island is the Dominican Republic.
About Haiti: (from the CIA World Factbook) Area: 27,750 sq km (slightly smaller than Maryland)
Population: 9,893,934 (2013 estimate)
Median age: 21.9 years old
Ethnic Groups: Black 95%, mulatto and white 5%
Religion: Roman Catholic 80%, Protestant 16% (Baptist 10%, Pentecostal 4%, Adventist 1%, other 1%), none 1%, other 3%
GDP: $13.15 billion (2012 est.)
GDP per capita: $1,300 (2013 est.)
Unemployment: 40.6% (2010 est.)
Timeline: 1492 - Christopher Columbus lands on the island and names it Hispaniola.
1697 - Spain recognizes France's claim to the western third of the island.
1791 - Slaves rebel against plantation owners. Toussaint L'Ouverture, a former slave, takes control and writes a constitution.
January 1, 1804 - Haiti gains independence from France. Haiti is the second oldest independent nation in the Western Hemisphere after the U.S.
1804-1915 - Over 70 different dictators rule Haiti.
1915 - U.S. President Woodrow Wilson sends Marines to Haiti to restore order. The U.S. occupies Haiti until 1934.
1946 - Army officers take control of Haiti's government.
1949 - Army officers take control of the government again after rioting breaks out.
1950 - Army officer Paul Magloire is elected president.
1956 - Magloire resigns after rioting breaks out; the army takes control of the government again.
1957 - Francois "Papa Doc" Duvalier, a doctor, is elected president.
1964 - Duvalier declares himself president for life and rules as a dictator.
1971 - Haiti's constitution is amended to allow the president to choose his successor. Duvalier chooses his son, Jean-Claude, who is 19.
April 1971 - After his father dies, Jean-Claude "Baby Doc" Duvalier declares himself president for life. He uses a secret police force called "Tontons Macoutes" (bogeymen) to enforce his policies.
1986 - Duvalier flees the country after a revolt. Lieutenant General Henri Namphy runs the country and tries, but fails, to get rid of the Tontons Macoutes.
March 1987 - A new constitution that calls for presidential and national assembly elections by the people is adopted.
November 29, 1987 - Elections are canceled after terrorist attacks on polling places. They are rescheduled for January 1988, and the people elect a civilian president and a parliament.
June 1988 - Namphy overthrows the new government and declares himself the president of the military government.
September 1988 - Officers of the Presidential Guard seize power from Namphy. Lieutenant General Prosper Avril declares himself president.
March 1990 - Avril resigns due to protests.
December 1990 - Jean-Bertrand Aristide wins Haiti's first free election.
September 1991 - Aristide is ousted in a military coup and flees the country. The Organization of American States and the United Nations lead trade boycotts to force Aristide's return to power. Many Haitians try to flee to the U.S. but are forced back to Haiti. Later the refugees are sent to Guantanamo Bay, Cuba.
July 3, 1993 - The military government agrees to allow Aristide to return and restore his government by October 30. They later back out of the agreement and do not allow Aristide to return.
September 17, 1994 - U.S. President Bill Clinton sends a delegation to Haiti in hopes of avoiding a military conflict. The team includes former U.S. President Jimmy Carter, Gen. Colin L. Powell, and Senator Sam Nunn. A peace deal does prevents an outbreak of fighting.
September 18, 1994 - The U.S. sends troops to Haiti to maintain order. The first 3,000 troops land on September 19 in Port-au-Prince and are from the Army's 10th Mountain Division, based in Fort Drum, New York.
October 1994 - Aristide is restored to power, while U.S. troops stay in Haiti to maintain order. The U.N. and OAS boycotts end, and the refugees at Guantanamo Bay return to Haiti.
March 1995 - Most U.S. troops leave Haiti.
Late 1995 - Rene Preval, a member of Aristide's Lavalas coalition, is elected president.
April 1996 - The last of the U.S. troops leave.
December 1998 - U.N. peacekeepers withdraw.
November 2000 - Aristide is elected president again; most other parties boycott the elections and claim they are fraudulent.
February 2004 - Rebels and political opposition leaders oppose Aristide's leadership and methods and want him to be removed from power. Aristide says he will remain in office until the last day of his term, February 7, 2006.
February 8, 2004 - Looting and violence spread throughout Haiti.
February 21, 2004 - An International assessment team made up of officials from the United States, France, Canada, Caricom (the Caribbean Community) and the Organization of American States arrive in Haiti to present Aristide with a peace plan. He accepts the terms of the plan, which include the appointment of a new prime minister, the establishment of a bipartisan cabinet, the holding of new elections to be overseen by international observers and the disarmament of militias, stationed in much of the north. The opposition leaders announce the rejection of any plan that does not include the immediate resignation of Aristide.
February 25, 2004 - President George W. Bush states that any Haitians attempting to enter the U.S. will be turned back by the Coast Guard, and urges the U.N. to compile an international security presence there.
February 29, 2004 - President Aristide leaves for the Central African Republic. Supreme Court Chief Justice Boniface Alexandre replaces him as the nation's president in a transitional government, as mandated by Haiti's constitution.
March 2004 - American and French troops deploy as part of a multinational peacekeeping force.
March 2, 2004 - Haitian rebel leader Guy Philippe declares himself the country's new police chief and calls for the re-establishment of Haiti's army, which Aristide disbanded in 1991. The U.S. does not recognize Philippe as the head of the Haitian police.
March 9, 2004 - Gerard Latortue, a 69-year-old international business consultant, is named the new prime minister of Haiti by the U.S.-backed Council of Sages.
April 2004 - The U.N. Secretary-General recommends the creation of a multidimensional stabilization operation to assist with the situation in Haiti. The operation is called the United Nations Stabilization Mission in Haiti (MINUSTAH).
June 2004 - A U.S.-led multinational force turns over authority in Port-au-Prince to U.N. Peacekeepers.
February 7, 2006 - After multiple scheduling delays and allegations of election fraud, Rene Preval is elected president of Haiti.
February 2007 - President Preval has the force of 8,000 U.N. Peacekeepers in Haiti begin an offensive against the street gangs in Port-au-Prince.
January 12, 2010 - A 7.0 magnitude earthquake strikes 14 miles west of Haiti, destroying most of the capital of Port-au-Prince. The estimated death toll ranges between 230,000 and 316,000.
October 21, 2010 - A cholera outbreak is confirmed in Haiti.
November 28, 2010 - The presidential election is held.
December 2010 - The electoral council announces that former first lady Mirlande Manigat has won but lacks the majority of votes needed for an outright victory. The runoff is scheduled for March 20, 2011.
January 16, 2011 - Former dictator Jean-Claude "Baby Doc" Duvalier unexpectedly returns to Haiti after almost 25 years in exile.
March 20, 2011 - The second round of presidential elections takes place.
April 4, 2011 - Preliminary results in the presidential runoff election show musician Michel "Sweet Micky" Martelly with 67.6% of the vote compared to former Haitian first lady Mirlande Manigat's 31.5%.
April 20, 2011 - Michel Martelly is officially declared the president of Haiti by the country's electoral council.
May 14, 2011 - Michel Martelly is sworn in as the president of Haiti.
June 8, 2011 - Heavy rain in Haiti leads to an increase in reported cases of cholera. As of October 26, 2011, more than 485,000 cases have been reported since the October 2010 outbreak, including 6,700 deaths.
July 2011 - According to a U.S. Centers for Disease Control and Prevention report, U.N. peacekeepers from Nepal most likely caused the October 2010 cholera epidemic.
October 2011 - A new CDC report details improvements made in sanitation and education that lowered the mortality rate from cholera in Haiti from 4 percent to below 1 percent. Since December 2010, fewer people are dying from the disease despite an increase in number of cases reported.
November 8, 2011 - Haitian cholera victims have filed a petition with the United Nations demanding compensation for their suffering, the victims' lawyers announced. Haitians who were sickened are demanding $50,000 each; families of those who died are seeking $100,000.
April 14, 2012 - The Haitian government and the World Health Organization launch a cholera vaccination program targeting 100,000 people.
September 4, 2012 - Hurricane Isaac is blamed for the deaths of 19 people in Haiti.
October 2012 - Dozens die in floods and landslides due to Hurricane Sandy.