Obama’s familial connections to the East African nation were on display as soon as Air force One touched down in Nairobi.
He was met at the airport by his half-sister, Auma Obama, who was born to his father’s first wife
The pair shared a warm embrace, before heading to a hotel where America’s first black president met more members of his extended family for dinner.
Among those at the dinner were his step-grandmother, Mama Sarah, whom he calls “Granny”.
Obama is linked to his Kenyan family via his father Barack senior, a pipe-smoking economist who Obama has admitted he “never truly” knew.
He walked out when Obama was just two and died in a car crash in Nairobi in 1982, aged 46.
Obama senior had worked in the government of Jomo Kenyatta, who led Kenya at independence from Britain until his death 14 years later in 1978.
The two men did not get on well, with Kenyatta — the father of Kenya’s current president Uhuru Kenyatta — sacking Obama senior, and blackballing him for further government jobs, an ostracisation that would help fuel alcoholism.
This is his first trip to Kenya since becoming president.
Kenya is a vital ally of the West in the battle against the Somali Islamist group al Shabaab, and Obama is likely to focus talks in Nairobi on security cooperation.
The al Qaeda-linked group was behind an attack on Nairobi’s upscale Westgate shopping centre in 2013, killing at least 67 people, as well as an attack in April at a Kenyan university near the Somali border that left 148 people dead.
In Nairobi, Obama will preside at a Global Entrepreneurship Summit, pay tribute to victims and survivors of the 1998 U.S. embassy bombing and dine with President Uhuru Kenyatta, whose indictment by the International Criminal Court for crimes against humanity largely barred Obama from visiting sooner. Charges have been dropped.
Deputy President William Ruto, still facing similar charges in The Hague-based court, was not at the airport reception ceremony. He denies having had a role in fomenting violence after the disputed 2007 election.
In the year before that vote, Obama visited Kenya when he was still a senator.
On this trip as president, he is not expected to travel to the village most closely associated with the family name and where his father is buried.