The day Barack Obama was sworn in as the 44th US president was a historic occasion for the United States. On January 20, 2009, more than 230 years after its foundation, the country had its first non-white commander in chief. "At Last," pop icon Beyonce sang at the inaugural ball as the president and his wife, Michelle, had their first dance as POTUS and FLOTUS.

Obama began his first term amid one of the most severe economic crises since the Great Depression. The US real estate bubble had just collapsed after Lehman Brothers declared bankruptcy, triggering a worldwide economic recession. Only days after he was sworn in, Obama signed a stimulus bill into law, including tax reductions and infrastructure investments worth almost $800 billion.

In March 2010, Obama fulfilled one of his central campaign promises: He signed the Affordable Care Act. It provides some 20 million Americans with health care coverage, according to the Department of Health. A controversial piece of legislation, "Obamacare" faced several legal challenges and Obama's successor, Donald Trump, vowed to gut the law he's called a burden for Americans.

After less than a year in office, the Nobel Committee awarded Obama the Nobel Peace Prize "for his extraordinary efforts to strengthen international diplomacy and cooperation between peoples." Criticism was widespread of granting the accolade to a sitting president conducting two wars and an expanded drone program that led to the deaths of hundreds of civilians.

After a decade of hunting, Osama Bin Laden, the al Qaeda leader thought to be responsible for the September 11, 2001 attacks, was killed by US military in Pakistan in May 2011. Obama announced this to the world in a televised address. But bin Laden's death did not remove the specter of terrorism from his presidency. In 2014, the US started a campaign of airstrikes against the "Islamic State."

Obama started his presidency with a promise to "reset" US-Russian relations, even taking then-President Dmitry Medvedev out for burgers in 2010. But the annexation of Crimea in 2014, Moscow's military support for Syrian President Bashar al-Assad's regime and accusations of Russians hacking the US election led to a strained relationship between the two nuclear powers.

In June 2012, Obama signed an executive order allowing young, undocumented immigrants studying in the US or who had served in the military to stay in the country. Four years later, the Supreme Court blocked the order with a 4-4 vote. Facing a Republican-led, confrontational Congress, Obama often turned to executive orders to push his policy agenda.

In November 2012, Obama celebrated another electoral victory - though he won by a narrower margin against Mitt Romney than he had against John McCain in 2008. In his second inaugural address, he set goals for his administration that included promoting LGBT rights, protecting the environment, immigration reform and gun control.

Obama was the first US president to endorse same-sex marriage. While he had previously favored civil unions, he first spoke out in favor of gay marriage during his 2012 campaign. When the Supreme Court ruled that same-sex marriage should be legal in June 2015, the White House was lit in rainbow colors in solidarity with the LGBT pride movement.

Obama revived the United States' relationship with its long-embargoed neighbor Cuba. When he visited the island in March 2016, he became the first president to set food in Cuba in 88 years. In late 2014, Cuban President Raul Castro and Obama had announced that they would re-establish diplomatic ties. Obama lifted travel restrictions and reopened the US embassy in Havana.

Whether he "slow jammed the news" with late night TV host Jimmy Fallon or sat "Between Two Ferns" with Zach Galifianakis, the president - a skilled speaker with impeccable timing - continuously stole the show from comedians. His White House Correspondents' Dinner speeches often had the room roaring with laughter - like when his "anger translator" joined him on stage in 2015 (pictured).

Obama appointed two women to serve on the US Supreme Court - Elena Kagan and Sonia Sotomayor. The latter (pictured) was the first Hispanic to sit on the country's highest court. This brought the number of female justices to a record three out of the nine. Obama saw his third pick for the court held up when the Senate refused to hold confirmation hearings for Merrick Garland.

Obama's election was often referred to as the beginning of a "post-racial" America, but Obama's initial hesitancy to address racial tension left many disappointed. In March 2015, he spoke in Selma, Alabama, commemorating progress made there 50 years earlier when police beat peaceful protesters, but also admitting the march for equal rights had not ended.

Despite an executive order signed on his second day as president, Obama was unable to keep promises to close the US military prison located at Guantanamo Bay, Cuba. The site of torture and detainment without trial for over a decade, Obama said the US compromised its most precious values at Gitmo. In the waning days of his presidency, further inmates were released, but several dozen still remain.