Referring to the Vatican, Pope Francis told the faithful in St Peter's Square that the new cardinals were "from every continent" and "show the indelible tie with the Church of Rome to churches in the world".
In addition to the 15 new cardinals who are under 80 and thus eligible to vote for the next Pope, Francis bestowed the honour on five other churchmen older than that who had distinguished themselves through their work in the Vatican bureaucracy and diplomatic service.
He also made another surprise announcement: that on February 12-13, he will lead a meeting of all cardinals to "reflect on the orientations and proposals for the reform of the Roman Curia", the Vatican's administrative bureaucracy.
Francis is using his papacy, which began in March 2013, to root out corruption, inefficiency and other problems in the curia.
No Americans or Canadians
The pope, who has undertaken a reform of the Vatican's administrative body known as the Curia, named only one cardinal from within it: Archbishop Dominique Mamberti, a Frenchman. He used to serve as the Vatican's foreign minister.
No American or Canadian cardinals were named, which Vatican spokesman Father Federico Lombardi said was because "their numbers are already consistent and remained stable."
Once these new members of the College of Cardinals are officially installed on February 14, there will be 228 members, including 125 who can vote in conclaves.
The new cardinals reflect a change in church demographics, which have shifted toward Africa, Latin America and Asia in the past century.
In 1910 about 65 per cent of the world's Catholics lived in Europe with 24 per cent in Latin America and the Caribbean, according to a 2010 study from American think tank Pew Research Center.
By 2010 Latin America accounted for 39 per cent of the church's followers while 16 per cent were in Africa and 24 per cent were in Europe.
Despite the new nominations, the overwhelming number of cardinals named during this and the previous two papacies have been Europeans. Over the three papacies, 57 are from Europe, 19 from Latin America and 15 from Africa, 14 from Asia and three from the Pacific.
These are the 20 new cardinals, grouped by region:
Europe:
Archbishop Dominique Mamberti of France
Archbishop Francesco Montenegro of Italy
Archbishop Luigi De Magistris of Italy (Non-voting)
Archbishop Ricardo Blazquez Perez of Spain
Archbishop Karl-Joseph Rauber of Germany (Non-voting)
Archbishop Edoardo Menichelli of Italy
Archbishop Manuel Jose Macario do Nascimento Clemente of Portugal
Africa:
Bishop Arlindo Gomes Furtado of Cape Verde
Bishop emeritus Julio Duarte Langa of Mozambique (Non-voting)
Archbishop Berhaneyesus Demerew Souraphiel of Ethiopia
Asia/Pacific:
Archbishop Charles Maung Bo of Myanmar
Archbishop John Atcherley Dew of New Zealand
Archbishop Francis Xavier Kriengsak Kovithavanij of Thailand
Bishop Soane Patita Paini Mafi of Tonga
Archbishop Pierre Nguyen Van Nhon of Hanoi
Latin America:
Archbishop Daniel Fernando Sturla Berhouet of Uruguay
Archbishop Alberto Suarez Inda of Mexico
Bishop Jose Luis Lacunza Maestrojuan of Panama
Archbishop Jose de Jesus Pimiento Rodriguez of Colombia (Non-voting)
Archbishop emeritus Luis Hector Villaba of Argentina (Non-voting)
- additional reporting AFP