The 1800s, and the birth of the industrial revolution, is deemed by many historians to have been the beginning of a sexual revolution also. More and more people were pushed together in densely populated areas, and attitudes to sex began to become more liberal. The 1960s also acted as a catalyst for increased sex due to the invention of the birth control pill, enabling women and men to have the opportunity to act on impulse and have sex for pleasure, as opposed to having sex for procreation alone.
Of course not all countries and cultures have evolved and developed sexual liberalisation at an equal rate. Ireland for example, prohibited the sale of condoms from 1935 to 1978 due to heavy influence from the Catholic Church. There has also been evidence to suggest that the number of sexual partners varies in different regions. Swedish people generally have many partners, while the Chinese tend not to have many.
