The princess is the fourth in line to the throne.
Prince William and the Duchess of Cambridge just unveiled the name of their second child and fourth in line to the throne.
Her name is Charlotte Elizabeth Diana.
The Duchess of Cambridge, previously known as Kate Middleton, gave birth at the Lindo Wing of St. Mary's hospital on Saturday morning.
The royal baby was born at 8:34 a.m. (3:34 a.m. ET) after Middleton was admitted to the hospital at 6 a.m. (1 a.m. ET).
The baby weighed 8 pounds 3 ounces. The couple wanted to wait to publicly announce the baby's name until they had told the Queen.
The names Alice and Charlotte were touted as British bookmakers' favourite for the baby's name, followed by Victoria, Olivia, and Elizabeth.
Charlotte is also the middle name of the Duchess of Cambridge's sister Pippa Middleton. Elizabeth is the name of the Queen and the Queen's mother. Diana is an homage to Prince William's mother, who died in a car crash in 1997 age 36.
At 2 p.m. (9 a.m. ET), soldiers from The King's Troop Royal Horse Artillery rode out in a procession from Wellington Barracks, near Buckingham Palace, to mark the birth of the Duke and Duchess of Cambridge's baby girl.
A volley of 62 shots was sounded in Hyde Park and near Tower Bridge to honour the arrival of Princess Charlotte.