George, the son of Prince William and his wife, Kate, was christened by Archbishop of Canterbury Justin Welby at the Chapel Royal at St. James's Palace.
The infant, who was born July 22 and is third in line for the British throne, wore a replica of an intricate lace and satin christening gown made for Queen Victoria's eldest daughter and first used in 1841.
He arrived at the chapel in his father's arms with his mother by their side, and appeared to wave at his great-grandmother, Queen Elizabeth II, although it was really a case of William moving his son's hand up and down.
Kate, smiling broadly on her way into the chapel, wore a cream-colored dress and matching hat with her long hair brushed to the side. William wore his customary dark suit and tie as he proudly carried their child.
The queen and her husband Prince Philip attended the event, along with Prince Charles, his wife Camilla, Prince Harry and other royals. Kate's parents Michael and Carole Middleton and her sister Pippa and brother James were also there.
Pippa Middleton read from the Gospel of St. Luke and Prince Harry read from the Gospel of St. John, palace officials said.
The two hymns were "Breathe on Me, Breath of God" and "Be Thou My Vision."
The seven godparents were also present. They are: Oliver Baker, a friend from St. Andrews University; Emilia Jardine-Paterson, who went to school at the exclusive Marlborough College with Kate; Hugh Grosvenor, who is the son of the Duke of Westminster; Jamie Lowther-Pinkerton, a former private secretary to the couple; Julia Samuel, described as a close friend of the late Princess Diana; Zara Phillips, who is William's cousin; and William van Cutsem, a childhood friend of William.
Palace officials said water from the River Jordan - where Christians believe Jesus Christ was baptized - would be used for the christening. The river's waters have often been used to make the sign of the cross on the heads of royal infants.
In Israel hours before the London christening, busloads of Russian tourists descended Wednesday morning on Qasr el-Yahud to immerse themselves in the River Jordan. The site - five miles (eight kilometers) east of Jericho - is considered Christianity's third holiest site after Bethlehem and Jerusalem
Charles and Camilla plan to host a private tea after the christening at their Clarence House residence.
Some royal watchers camped outside the palace for more than 24 hours to obtain a good vantage point for watching the guests arrive, but the ceremony was private.
William and Kate hired photographer Jason Bell to take official pictures, which are expected to include a historic multi-generational photograph of the queen with three future monarchs: her son Charles, her grandson William and her great-grandson George.
The official photographs are expected to be released to the public on Thursday.