On this day in 1900, the 169 islands collectively known as the Kingdom of Tonga, or the Friendly Islands, in the South Pacific, were annexed by Britain.
On this day in 1906, the 19-kilometer Simplon Tunnel linking Italy and Switzerland through the Alps was officially opened.
On this day in 1956, the world's first intercontinental ballistic missile (ICBM) was put on public display in the United States.
On this day in 1980, the long-dormant Mt. St. Helens in southwestern Washington State exploded, killing 22 people.
On this day in 1994, Jacqueline Kennedy Onassis, former First Lady of the United States from 1961 to 1963, died at the age of 65. She promoted the arts and supervised the redecoration of the White House. In 1968, five years after President John F. Kennedy's assassination, she married shipping tycoon Aristotle Onassis.