Addressing a crowd expected to be half the 1.8 million who made a pilgrimage to Washington for his swearing-in four years ago, Mr Obama will try to set a purposeful tone for his final four years in power.
"This country has gone through some very tough times before," he said in a video message released by the White House in advance of the ceremony, "but we always come out on the other side."
He said there was "nothing that can stop America" when its people had a "fair shot" to "get a great education, get a good job, look after their kids and get some basic security".
Mr Obama will speak on Martin Luther King Day, 50 years after the civil rights leader's rousing address at the end of his march on Washington.
As he is sworn in by the Chief Justice of the Supreme Court, he will place his left hand on two bibles used by King and by Abraham Lincoln.
Having prompted comparisons with the glamour of John F Kennedy's 'Camelot' by dancing with his wife Michelle into the early hours of his first day as president at 10 different inaugural balls, Mr Obama will attend just two this time before retiring for the night.
He will speak to a nation scarcely less bitterly divided than when he promised "unity of purpose over conflict and discord" in 2009.
He must then resume bad-tempered negotiations with Republicans, who control half of Congress and fiercely oppose his agenda. A poll by Rasmussen this week found that 58pc of Americans planned to watch the inauguration, down from 75pc in 2009.
Before Monday's ceremony, Mr Obama will be sworn in on Sunday in a closed service in order to satisfy the US Constitution's requirement that presidents be officially inaugurated on January 20. (© Daily Telegraph, London)