The 70-year-old will cover more than 18,000 kilometres acrossAlgeria,Cameroon,AngolaandEquatorial Guineadelivering 11 speeches and presiding over seven masses before returning on 23 April.
From conflict and human rights to migration and corruption, the US-born pontiff is expected to address a range of issues during a visit that comes at a time of global uncertainty linked to theMiddle Eastwar and its economic impact.
It will be his third trip outsideItalysince his election in May, after visits to Turkey and Lebanon last year, and Monaco in March.
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Historic Algeria visit
Leo will become the first pope to visit Algeria, where Islam is the state religion.
He is due to meet President Abdelmadjid Tebboune, visit the Great Mosque of Algiers and travel to Annaba, home of Saint Augustine, where he will meet members of the Augustinian order. He is also expected to pay tribute to migrants killed in shipwrecks trying to reachEurope.
The pope is a brother who comes to visit his brothers, Cardinal Jean-Paul Vesco, the archbishop ofAlgiers, told French news agency AFP.
Leo will also pray privately for 19 priests and nuns killed during Algerias 1992-2002 civil war, known as the Black Decade.
Ahead of the visit, three international NGOs called on Pope Leo to raise concerns about the treatment of religious minorities with Algerias authorities.
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Peace focus in Cameroon
In Cameroon, the pope is expected to focus on peace and reconciliation, particularly in the conflict-hit, English-speaking northwest of the country.
He will lead a peace meeting and hold a mass in Bamenda, the centre of the violence, under heavy security.
To see His HolinessPope Leo XIVarrive in Cameroon, for us who are Catholic Christians, it further strengthens our faith, it further strengthens our ties with our God, Simon Pierre Ngombo, aCatholicworshipper, told the Associated Press.
It is a perfect moment to touch each others hearts.
Leo will also meet with PresidentPaul Biya, 93, one of the worlds longest-serving heads of state, and visit hospitals, schools and charities run by the Catholic Church.
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Inequality in oil-rich Angola
In Angola, thePopeis expected to address poverty and corruption in a country rich in oil and minerals but marked by deep inequality, after a long civil war that ended in 2002.
He will visit the capital Luanda, where wealthy neighbourhoods sit alongside vast slums, and travel to Muxima, one of the holiest sites in southernAfrica.
He is expected to call for a more equitable distribution of wealth from natural resources.
However, not everyone believes the pope's visit will benefit ordinary Angolans.
At the societal level, it represents nothing, because millions of dollars will be taken from the state treasury to prepare, without bringing any benefits to our country, Rosa Kanga, a 42-year-old teacher, told AFP.
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Balancing act in Equatorial Guinea
The final leg of the tour in Equatorial Guinea will see Pope Leo meetPresident Teodoro Obiang Nguema Mbasogo, who has ruled since 1979.
Around 80 percent of the countrys population is Catholic, but only one pope has visited before now nearly half a century ago.
The visit is expected to require a careful balance between supporting local Catholics and avoiding any perception of backing the government.
Many expect the pope to address human rights and social justice in the country.
In Malabo, large images of the pontiff have been displayed across the city, with state television broadcasting coverage of the visit ahead of his arrival.
(with newswires)
Originally published on RFI
