There is no consensus on where the cucumber originally came from: some believe it is native to India - from the slopes of the Himalayas. It could be, however, that cucumbers have existed much longer and are actually native to South Asia before they were brought to India. In any case, we do know they were cultivated at least 4000 years ago.
Generally, a distinction is made between cucumbers and gherkins (pickled cucumbers). Based on the colour and shape of cucumbers it may come as a surprise to know they are actually berries.