Archbishop Pietro Parolin, 58, currently nuncio in Venezuela, will become the Vatican's secretary of state – effectively the Pope's prime minister – on October 15, replacing Cardinal Tarcisio Bertone, 78, who has been beset by a series of scandals, culminating in the theft and leaking of papal documents last year.
The Italian son of a farming equipment salesman and primary schoolteacher, Archbishop Parolin has served in Vatican embassies in Nigeria and Mexico and has worked on relations with Vietnam and China, as well as serving as the Vatican's deputy foreign minister from 2002 to 2009.
He brings a reputation as a good administrator and linguist, compared to Cardinal Bertone who lacked diplomatic experience and did not speak English.
"I feel the full weight of the responsibility placed upon me: this call entrusts to me a difficult and challenging mission, before which my powers are weak and my abilities poor," Archbishop Parolin said in a statement.
Cardinal Bertone, appointed in 2006 by Pope Benedict XVI, should have stepped down upon turning 75, but was kept on, reportedly to the displeasure of a rival faction of bureaucrats within the Vatican's walls.
Critics had also accused him of favouritism and making poor choices in a series of key Vatican appointments, while diplomats complained of a lack of papal access.
Under his watch, the Vatican suffered a number of gaffes and scandals, including Benedict's naming in 2007 of a Polish archbishop, only for the appointment to be immediately scrapped over the man's cooperation with the Polish Communist secret police. Two years later, Benedict lifted the excommunication of an holocaust denying bishop, Richard Williamson, before claiming he would have had a better idea of Williamson's views if a check on the internet had been carried out.
This year has seen the resignation of the Vatican bank's director and deputy director – both considered close to the secretary of state – due to a money laundering inquiry.
Archbishop Parolin is unlikely to have the same free hand at the Vatican enjoyed by Cardinal Bertone. The Pope is due to convene in the coming months an advisory board of eight cardinals to help him introduce reforms of the Vatican's notoriously secretive bureaucracy. He has also set up further commissions to advise him on how to reform the Vatican bank and advise in improving transparency.
Gianni Valente, writing for the Vatican Insider website, said the appointment would ensure the Church "will once again be well placed to offer its wisdom and foresight in order to promote peace" in the world.
The appointment however earned criticism from SNAP, a group which campaigns against priestly paedophiles, and which noted that the Pope's reform agenda has yet to bear fruit, five months into his papacy.
"Pope Francis can ride buses and carry luggage and discuss poverty every single day. But that won't make kids safer. Tinkering at the edges of unhealthy, entrenched Vatican complicity isn't enough," it stated.