Pope Francis called on the world to end the "hatred and vengance" in Syria and to "heal the wounds of the beloved country of Iraq" in his first Christmas Day speech to an estimated crowd of 150,000 at the Vatican on Wednesday.
In an address dominated by calls to end international conflicts, the pope urged "a favorable outcome in peace talks between Israel and Palestine."
He also highlighted the conflicts in South Sudan and the Central African Republic, which he said had been "torn apart by a spiral of violence and poverty."
The message of the birth of Jesus in Bethlehem was directed at "every man or woman who keeps watch through the night, who hopes for a better world, who cares for others while humbly seeking to do his or her duty," he said.
His words were met with chants of support from the large crowd in St. Peter's Square, where flags from all over the world were waved.
"Prince of Peace, in every place turn hearts aside from violence and inspire them to lay down arms and undertake the path of dialogue," he told the crowd, in Italian.
The pope spoke of violence in Nigeria -- "rent by constant attacks which do not spare the innocent and defenseless" -- and of refugees in the Horn of Africa and the Democratic Republic of Congo. "May tragedies like those we have witnessed this year, with so many deaths at Lampedusa, never occur again."
He added: “Child of Bethlehem…look upon the many children who are kidnapped, wounded and killed in armed conflicts, and all those who are robbed of their childhood and forced to become soldiers.”
He asked for protection for victims of natural disasters, including those affected by Typhoon Haiyan, which smashed into the Philippines in November, killing more than 6,000 people and displacing millions.
Related: Then and now photos show differences in Benedict's, Francis' styles
On Tuesday, Pope Francis celebrated Christmas Eve Mass at St. Peter’s Basilica, where he quoted from Isaiah: "The people who walked in darkness have seen a great light."
Elsewhere on Christmas Day, Britain's Queen Elizabeth II and other members of the Royal Family arrived at St Mary Magdalene church, in Sandringham, where they attended an annual Christmas service, the BBC reported.
Later on Wednesday, the Queen's traditional Christmas message focused on the need to to pause for reflection.
"We all need to get the balance right between action and reflection," she said in the message, which was prerecorded earlier in December at Buckingham Palace.
"With so many distractions, it is easy to forget to pause and take stock."
U.K. Prime Minister David Cameron tweeted: "I wish everyone in Britain and around the world a very happy and peaceful Christmas,” and posted a link to him reading the poem "A Visit from St. Nicholas."
President Barack Obama used his Christmas message to call on Americans to embrace the season in service and "to love our neighbors as we would ourselves; to feed the hungry and look after the sick; to be our brother’s keeper and our sister’s keeper."
In the Mideast, pilgrims celebrated Christmas in the ancient Bethlehem church where tradition holds Jesus was born, as candles illuminated the sacred site and the joyous sound of prayer filled its overflowing halls.
This year's turnout was the largest in years in Bethlehem, and the celebrations have been marked by careful optimism amid ongoing Israeli-Palestinian peace talks. Leaders expressed hope the coming year would finally bring the Palestinians an independent state of their own.
The top Roman Catholic cleric in the Holy Land, Latin Patriarch Fouad Twal, led a prayer for some 1,000 worshippers. "The whole world now is looking at Bethlehem, the birthplace of Jesus," Twal said in his annual address.
"The message of Christmas is a message of peace, love and brotherhood. We have to be brothers with each other," he said.
Among the crowds was New Yorker Will Green, who traveled to the town with his wife Debbie and 2-year-old daughter Daphne.
"All the stories that we grew up with, it's here," he told The AP. "It's part of our life. We heard them in the family, school and church. This is the birthplace."
The Associated Press contributed to this report.
Related: