Bangladesh is one of the world's most densely populated countries, with its people crammed into a delta of rivers that empties into the Bay of Bengal.
Poverty is deep and widespread, but Bangladesh has in recent years reduced population growth and improved health and education.
Formerly East Pakistan, Bangladesh came into being only in 1971, when the two parts of Pakistan split after a bitter war which drew in neighbouring India.
Bangladesh spent 15 years under military rule and, although democracy was restored in 1990, the political scene remains volatile.
Islamist extremism has been rising in the usually tolerant country.
The low-lying country is vulnerable to flooding and cyclones, and stands to be badly affected by any rises in sea levels.