At 39, the pro-EU former investment banker will become France’s youngest-ever President

After a resounding victory in Sunday’s runoff, Emmanuel Macron will be sworn in as France’s next President at the Elysee palace on May 14, outgoing President Francois Hollande said.

At 39, the pro-EU former investment banker will become France’s youngest-ever President. On Monday, Mr. Macron’s laid the groundwork for his transition to power, announcing a visit to Germany and a name change for his political movement and appearing with his predecessor at a solemn World War II commemoration, even as the focus shifted to the challenges ahead for his administration.

His party is changing its name to La Republique En Marche (Republic on the Move) as it prepares a list of candidates for next month’s parliamentary elections. Mr. Macron has promised that half of those candidates will be new to elected politics, as he was before his victory on Sunday.

Mr. Macron won the presidency with 66% of votes against his far-right rival Marine Le Pen’s 34%, show the final numbers released by France’s Interior Ministry.

“I know the anger, the anxiety and the doubts that a large number of you have expressed,” Mr. Macron told thousands of cheering and flag-waving supporters at a victory party in the courtyard of the Louvre museum in Paris. “I will fight with all my strength against the divisions that are undermining us,” he said.

Mr. Macron, a former economy minister, has proposed an ambitious domestic reform agenda. He wants to ease rigid labour laws he believes fuel high unemployment, cut state spending, improve education in deprived areas and increase welfare protection to the self-employed.

World leaders from Donald Trump of the U.S. to Angela Merkel of Germany congratulated him on his victory. “Macron carries the hopes of millions of French people and also many in Germany and across Europe,” Ms. Merkel told reporters, saying she was “very pleased” by his victory.