Donald Trump is now the 47th president of the United States, as well as the 45th president, a businessman – and a man who knows how to put on a show.
A litany of former presidents, Trump family members, tech royalty and world politicians attended the historic event.
As he entered the Rotunda, where the inauguration ceremony was moved to due to freezing temperatures outside, he was met with cheers and applause.
He reached for his wife Melania, who he unsuccessfully tried to kiss, and greeted his predecessor, Joe Biden, who was standing opposite the Trump family with his wife, Jill, behind him and former vice president Kamala Harris beside him.
After being sworn in, the Republican gave a speech in which he announced some sweeping measures on migration, climate change and gender rights.
On the eve of his inauguration, Mr Trump held a final rally in Washington DC, where he hinted at a blizzard of executive orders he would sign once he was back in the Oval Office.
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He was joined on stage by Elon Musk, his new government efficiency tsar, and then had a boogie with none other than the Village People, as they sang their hit YMCA.
Elon Musk reacts as President Donald Trump speaks the night before his inauguration. Pic: AP
After a candlelit dinner at the National Building Museum, he headed back to Blair House, known as The President’s Guest House, to prepare for one of the biggest days in the US political calendar.
Donald Trump speaks the night before his inauguration at the Building Museum. Pic: AP
On Monday morning, the inauguration began. It started at St John’s Church, known as the “Church of the Presidents”.
Donald Trump’s vice president JD Vance and his wife Usha Vance arrive at St John’s Church. Pic: Reuters
It is one of the most private events of an inauguration, with no TV cameras allowed inside the small, yellow church.
Donald Trump greets his vice president JD Vance at St John’s Church. Pic: Reuters
Ivanka Trump looks after her sons Joseph and Theodore at St John’s Church. Pic: Reuters
After the intimate prayer service, incoming vice president JD Vance went to meet outgoing VP Kamala Harris with their respective partners at the White House.
VPs past and future – Kamala Harris (centre-right) and JD Vance (far right) – and their partners, Doug Emhoff and Usha Vance. Pic: AP
The Trumps headed to tea with the Bidens before the four of them were driven together to the swearing-in ceremony.
Donald and Melania Trump are greeted by former president Joe Biden and first lady Jill Biden at the White House. Pic: AP
When Joe Biden was sworn in four years ago, then president Trump did not afford him the same tradition and instead skipped the whole inauguration.
Members of the US Marine Band, The President’s Own, arrive before the inauguration. Pic: AP
While the 46th and 47th presidents took tea, the Rotunda filled with guests and musicians.
Meta chief executive Mark Zuckerberg ahead of the inauguration. Pic: AP
Guests arrive ahead of the presidential inauguration in the Rotunda. Pic: AP
Crowds of supporters brave the cold to watch a live broadcast of the ceremony. Pic: AP
On the streets of Washington, thousands gathered to watch it live on screens.
Read more: Everyone wants a piece of Trump outside inauguration
Former presidents filed into the room, Barack Obama on his own after his wife Michelle said she couldn’t attend.
Former Secretary of State Hillary Clinton and former President Bill Clinton arrive. Pic: AP
Former President George W Bush, former first lady Laura Bush and former President Barack Obama. Pic: AP
After the final guests had arrived, Vance entered to a fanfare by the military band.
He was followed by Mr Trump, ready to be sworn in with his hand on two bibles.
One was given to him by his mother in 1955, to “mark his Sunday Church Primary School graduation” and the other is the Lincoln Bible, first used in 1861 to swear in the 16th US president.
