During the campaign, Trump frequently told rally-goers about what he described as the horrors of the inner cities, the tragedy of the education system and the extent to which the United States was being taken advantage of around the globe, offering his leadership as an alternative.
"Mothers and children trapped in poverty in our inner cities, rusted-out factories scattered like tombstones across the landscape of our nation. An education system flush with cash but which leaves our young and beautiful students deprived of all knowledge," he told the crowd. "And the crime and the gangs and the drugs that have stolen too many lives and robbed our country of so much unrealized potential. This American carnage stops right here and stops right now."
As he also promised on the campaign trail, the buck stops with him.
"From this day forward, a new vision will govern our land. From this day forward, it's going to be only America first. America first. Every decision - on trade, on taxes, on immigration, on foreign affairs - will be made to benefit American workers and American families," Trump said in his roughly 16-minute inauguration speech, the shortest since President Jimmy Carter's in 1977.
"This moment is your moment. It belongs to you," he said. "It belongs to everyone gathered here today and everyone watching all across America."
He pledged to give voice to "the forgotten men and women" and called for a return of power to the American people from the politicians in Washington.
"I will fight for you with every breath in my body, and I will never let you down," he said.
And he sent a warning to lawmakers that he views as ineffectual.
"In America, we understand that a nation is only living as long as it is striving. We will no longer accept politicians who are all talk an no action, constantly complaining but never doing anything about it. The time for empty talk is over. Now arrives the hour of action."
Trump closed his speech with his oft-repeated campaign slogan.
"Together we will make America strong again. We will make America wealthy again. We will make America proud again. We will make America safe again. And, yes, together, we will make America great again," he exclaimed.
After the inauguration ceremony, the Trumps escorted the Obamas to a waiting helicopter, which will take the former president and first lady to Joint Base Andrews, after which they headed to California.
Trump then signed several documents, including the waiver allowing retired Marine Gen. James Mattis to serve in his Cabinet, while surrounded by his family and political leaders. From there, the group went to the Statuary Hall in the Capitol for a luncheon before the parade.
While making brief remarks at the end of the luncheon, Trump said he was "very, very honored" that Bill and Hillary Clinton attended the inauguration, prompting a standing ovation for the pair.
"I have a lot of respect for those two people. Thank you for being here," he said.
The Trump family left the Capitol in a motorcade en route to the White House. They got out of the vehicle twice, walking for short stretches and waving to the crowds lining the street.
Trump faces a divided nation that is still reeling from the long and contentious presidential race. Hillary Clinton, Trump's general election rival, attended today's ceremony and was seated just a few rows behind Trump and members of his family.
Trump and Vice President Mike Pence were sworn in by Supreme Court Justice Clarence Thomas. Immediately after his swearing-in, Trump embraced members of his family and waved to the crowd on the National Mall.
Earlier in the day Trump participated in traditional inauguration customs, such as attending a church service at St. John's Episcopal Church.
Trump chose to wear his trademark red tie, and Melania Trump donned a custom-designed Ralph Lauren sky blue cashmere mock turtleneck dress with a matching cropped cashmere jacket and long suede gloves.
A Pointed MessagePastor Robert Jeffress of First Baptist Dallas led the service this morning at St. John's.
Jeffress is a familiar face to Trump and his eagle-eyed supporters; he appeared with Trump at many rallies on the campaign trail.
"I'm not going to lecture the new president," Jeffress said during an interview with Fox News on Thursday night.
Jeffress said he intends to "encourage" Trump by comparing him "to another great leader God chose."
"[God] told Nehemiah to build a giant wall around Jerusalem to protect the citizens, so I'm going to use Nehemiah's story as an example of why God blesses leaders," Jeffress said.
The service was closed to the media, but the Trump team's social media and senior adviser, Dan Scavino Jr., shared two tweets from the service.
Pence also posted pictures, including this one:
Rundown of the DayThe day's events followed the pattern of past inaugurations. The Trumps stayed overnight at Blair House, across the street from the White House.
Before the inaugural ceremony, the Trumps sat down for tea with the Obamas; Melania Trump presented them with a box from jeweler Tiffany & Co. Also at the White House were Mike Pence, Karen Pence, Vice President Joe Biden, Jill Biden, Senate Majority Leader Mitch McConnell, Senate Minority Leader Chuck Schumer, House Speaker Paul Ryan, House Minority Leader Kevin McCarthy and Minority Leader Nancy Pelosi.
Trump's Cabinet-level picks and former presidents were in attendance for the inauguration.
Bill Clinton and Hillary Clinton arrived at the Capitol together. Hillary Clinton, who won the popular vote by roughly 3 million ballots, wore white, a color that holds special significance for the suffragist movement.
Mixing Tradition With Personal TouchesTrump chose two Bibles for his swearing-in: his childhood Bible and President Abraham Lincoln's Bible. The only other president to use Lincoln's Bible was Barack Obama in 2009 and 2013.
Jackie Evancho, a 16-year-old "America's Got Talent" alum, sang the national anthem.
An abnormal facet of the day was the sizable number of congressional Democrats who announced they would skip the inauguration. The latest count had one-third of House Dems boycotting the ceremony. There was no modern precedent for a political boycott of that scale.