Trafalgar Square Authority in conjunction with the charity Unicef, who began ticketing the event to control crowd numbers. A Christmas ceremony has been held in the square every year since 1947. A Norway spruce (or sometimes a fir) is presented by Norway's capital city, Oslo as London's Christmas tree, a token of gratitude for Britain's support during World War II. (Besides war-time support, Norway's Prince Olav and the country's government lived in exile in London throughout the war.) The Christmas tree is decorated with lights that are switched on at a seasonal ceremony. It is usually held twelve days before Christmas Day.
Capitol Christmas Tree procedure was established for the installation of a yearly tree. The 1963 tree was a live Douglas-fir, purchased from a Pennsylvania nursery. It was re-decorated each year through 1967 when it was severely damaged in a wind storm and subsequently died as a result of root damage. After the 1963 tree died, white pines from Maryland were cut down and put on display for the 1968 and 1969 seasons. Beginning in 1970, trees have been provided by the U.S. Forest Service from various National Forests. The "Capitol Christmas Tree" is traditionally lit during a ceremony at the beginning of December,