The 44th President of the United States was sworn into his second term on Jan. 20 and delivered his inauguration speech, which included a historic nod to the gay rights movement, the following day.
Pope Benedict XVI became the first pope to resign since 1415 when the Vatican announced his retirement in February, citing his "advanced age" as explanation for his resignation.
"After having repeatedly examined my conscience before God, I have come to the certainty that my strengths, due to an advanced age, are no longer suited to an adequate exercise of the Petrine ministry," Pope Benedict XVI wrote in a declaration to the public.
Jennifer Lawrence's makeup artist posted this photograph of the actress being made up before her GIF-worthy Oscars win.
Cardinal Jorge Mario Bergoglio of Buenos Aires, Argentina, was elected to the Office of Pope in March following Pope Benedict XVI's resignation. Choosing the papal name Francis in honor of St. Francis of Assisi, he became the first Jesuit pope, as well as the first pope from the Americas.
Two deadly blasts erupted near the finish line at this year's Boston Marathon, killing three people and injuring 178. Both suspects were eventually identified and apprehended, as the nation stood in solidarity with the grieving city of Boston.
This hybrid donut and croissant created by the Dominique Ansel Bakery in New York City became a viral sensation, with would-be tasters waiting hours in line just to sample the goods.
A powerful cyclone tore through Moore, OK, destroying homes, vehicles and schools and claiming 51 lives.
Neil Patrick Harris's eight-minute opening number as host of the 2013 Tony Awards featured musical mashups from nominated shows, including Kinky Boots, Motown: The Musical and Pippin, but it was a cameo by former boxing champion Mike Tyson that really stole the show.
In a landmark ruling, the Supreme Court of the United States declared the 1996 Defense of Marriage Act unconstitutional, conferring federal benefits to same-sex couples that had previously been reserved for opposite-sex unions.
Following three days of violent protests, Egyptian military forces overthrew President Mohammed Morsi and replaced him with the head of the country's constitutional court. The transition was not a smooth one, however, and the nation continues to be rocked by protests and political upheaval.
Months after Superstorm Sandy pummeled Lower Manhattan, the Statue of Liberty, which had been closed since the storm, reopened on Independence Day.
Protests erupted around the nation when George Zimmerman was acquitted of second-degree murder and manslaughter in the fatal shooting of 17-year-old Trayvon Martin, prompting enraged Twitter users to create the hashtag #JusticeForTrayvon.
Duchess Kate gave birth to Prince George on July 22 as news outlets and social media eagerly awaited their first glimpse of the newborn. Kate and Prince William introduced the infant to the public -- as well as dozens of cameras -- the next day.
The Perseid meteorites burst through the Earth's atmosphere at speeds of 132,000 miles per hour, which made for a series stunning photographs of the comet fragments sailing through the night sky.
The Obamas introduced Sunny, their second Portuguese Water Dog, to the world via Twitter, along with a photograph of the pup playing with her new big brother, Bo.
Kanye West first revealed this photograph of daughter North West on Kardashian matriarch Kris Jenner's talk show. Kim Kardashian reposted the photo to Instagram, where it promptly made the rounds of every celebrity blog, like ever.
Before Miley's now-infamous VMA performance, she posted this tongue-wagging photograph of herself with her backup dancers.
Fifty years after Martin Luther King's March on Washington and his iconic "I Have a Dream" speech, delivered on the steps of the Lincoln Memorial, President Obama took to those same steps to commemorate Dr. King. This image from NBC News juxtaposes a photograph from that momentous occasion with the present-day gathering.
NASA inaugurated its Instagram account with this photograph of the Earth seen from the Moon, in honor of the launch of its Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft.
After bowing out of the U.S. Open in 2012 with an injured knee and losing to a low-ranked player at Wimbledon in June, Rafael Nadal staged a triumphant comeback at the 2013 U.S. Open, besting the top-seeded Novak Djokovic to win his 13th Grand Slam title.
A deranged gunman opened fire at the Naval Sea Systems Command Headquarters in Washington, D.C. Twelve victims perished, as did the shooter.
Nearly 1,500 consumers waited outside Apple's flagship store in New York City to purchase the new iPhone 5S, which sold out within the first 24 hours.
The United States government shut down as the U.S. House of Representatives and the Senate clashed over the Affordable Care Act. The government reopened on Oct. 17 with a bill that would raise the debt ceiling until Feb. 7.
Graffiti artist Banksy made New York his canvas for the month of October, festooning the city with graffiti and performance art.
On Oct. 30, 2012, Hurricane Sandy -- later upgraded to Superstorm Sandy -- swept through the Northeast, flooding low-lying portions of New York City and leaving as many as 8.5 million people without power. One year later, photographs depicting New York's recovery and revealing the work left to be done served to commemorate the event.
One of the strongest storms on record to make landfall, Typhoon Haiyan struck hardest in the coastal city of Tacloban and caused as many as 10,000 deaths.
In September, Twitter announced that it would be filing for an I.P.O., revealing plans to take the company public. One month later, the social media giant disclosed plans to list on the New York Stock Exchange. Twitter officially went public on Nov. 7 with the ticker symbol TWTR, closing at $44.90 per share.
In one of the most touching tales of the year, the Make-a-Wish Foundation set up a city-wide, Batman-themed adventure for Miles, a 5 year-old boy with leukemia. Nearly 15,000 San Franciscans signed on to help Miles enact his fantasy.
On the 50th anniversary of John F. Kennedy's assassination, CBS News streamed the original news broadcasts announcing his death, while PBS devoted an episode of American Experience to celebrating his life. This image by CBS This Morning depicts the John F. Kennedy Eternal Flame memorial at his gravesite.
Macy's held its 87th annual Thanksgiving Day Parade in New York City amid blustery weather, fortunately avoiding the worst of the storm that threatened Thanksgiving travel plans. The Snoopy and Woodstock balloon was a favorite among Instagrammers at this year's parade.
With Christmas music spilling from doorways and leafy surfaces everywhere wrapped in festive lights, it's only natural to begin thinking about what 2014 will bring.
The past year gave us political milestones like October's government shutdown and the repeal of the Defense of Marriage Act, as well as pop-culture talking points like Miley Cyrus's twerkmageddon and the ascendancy of the cronut to the foodie Pantheon. Some of these moments could be perfectly encapsulated in a photograph, and enhancing them with Amaro or Mayfair only served to make them more memorable.
See also: The 10 Types of Instagram Users
Before you rush off to compose your New Years' resolutions, take a look at our gallery of some of the most significant events of 2013 as they were captured on Instagram.
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Image: Flickr, Cristian Bortes