It is 150 years since the Battle of Gettysburg, a turning point in the American Civil War
The recent surge in violence in Iraq has echoes of the sectarian conflict in 2006-07
Novelist Colm Toibin recalls US President John F Kennedy's visit to Ireland in June 1963
It took until the 1950s for researchers to connect smoking with lung cancer
It is regarded as one of the most important pieces in 20th Century English music.
It's 55 years since a picture of a foetus inside the womb was first published.
It's 50 years since Soviet Cosmonaut Valentina Tereshkova went into orbit.
In June 1979 an American TV reporter was shot dead by government forces in Nicaragua
It is 40 years since the opening of a comedy musical which would become a cult phenomenon
It is 60 years since the American couple were executed for spying