The annual message, pre-recorded in Buckingham Palace Chapel this year, is one of the few occasions in the year when the queen speaks publicly about her views. It is also the one occasion in the year when the queen writes her own speech, without the government's involvement.
The address is broadcast around the country and to the Commonwealth of Britain's former colonies.
Following traditions, Britain's royal family gathered Sunday at the Sandringham estate in eastern England with a new addition at the annual festivities — Prince Charles' wife, Camilla. And a few dozen swimmers braved a dip in the chilly pond in London's Hyde Park on Sunday for the traditional Christmas Day swim.
"The day after my last Christmas message was broadcast, the world experienced one of the worst natural disasters ever recorded," the queen said, referring to the tsunami that crashed into coastlines from Asia to Africa one year ago, killing some 216,000 people.
The tsunami was followed by vicious hurricanes across the Caribbean, the devastation of New Orleans and pounding earthquakes in Pakistan and India.
"As if these disasters were not bad enough, I have sometimes thought that humanity seemed to have turned on itself — with wars, civil disturbances and acts of brutal terrorism," she said.
Suicide bombers targeted London's transit system in July, killing 56 people, including themselves on July 7. The bombings were followed by botched attacks two weeks later.
Terrorists also struck Jordan and Indonesia. Scores have died in suicide attacks in Iraq.
Praising relief and emergency workers of all faiths, the queen said 2005's string of tragedies offered opportunities for people of all faiths to unite and work together.
"This last year has reminded us that this world is not always an easy or a safe place to live in, but it is the only place we have," she said.
She also said the year's events gave cause for hope, reports CBS News' Larry Miller
"I believe also that it has shown us all how our faith — whatever our religion — can inspire us to work together in friendship and peace for the sake of our own and future generations."
The monarch's Christmas address is a tradition that began with her grandfather, King George V, who delivered the first one in 1939, at the outbreak of World War II.
The queen delivered her first Christmas speech on the radio in 1952, when she took the throne following the death of her father, King George VI. The broadcast was first televised in 1957.
As they have for many years, the queen and many of her relatives attended a church service near the Sandringham house.
About 1,000 well-wishers lined the path leading to St. Mary Magdalene Church, about 500 meters from Sandringham House.
Camilla, Duchess of Cornwall, walked to church with her husband and smiled at the people gathered along the way. They were joined by Princes William and Harry; the queen's husband Prince Philip, Duke of Edinburgh; Princess Anne, Prince Andrew, Prince Edward and members of their families. The queen arrived at the service by car.
The royals were greeted by the rector of Sandringham, the Rev. Jonathan Riviere, who conducted the service.
He prayed for the royal family — mentioning the queen, the Duke of Edinburgh, the Prince of Wales and "Camilla" by name.
The morning race in the Hyde Park's Serpentine pond attracted 57 swimmers who competed in a 100 meter race. Swimmers ranged from 12 to 82-years-old, with some dressed for the occasion in red Santa Claus hats.
The winner was Kevin Murphy, 56, who won the race for the first time after nearly 20 years of trying.
Murphy, from northwest London, said: "I'm absolutely delighted, but my feet hurt, my hands hurt, and I'm trying to get my brain in gear because I'm so cold."