[4][5] The grass snake is widely distributed in mainland Europe, ranging from mid Scandinavia to southern Italy.

Captive snakes have been observed taking earthworms offered by hand, but dead prey items are never taken.

The snake will search actively for prey, often on the edges of the water, using sight and sense of smell (using Jacobson's organ).

Grass snakes, like most reptiles, are at the mercy of the thermal environment and need to overwinter in areas which are not subject to freezing.

[6]As spring approaches, the males emerge first and spend much of the day basking in an effort to raise body temperature and thereby metabolism.

This may be a tactic to maximise sperm production, as the males mate with the females as soon as they emerge up to two weeks later in April, or earlier if environmental temperatures are favourable.

[6] After breeding in summer, snakes tend to hunt and may range widely during this time, moving up to several hundred metres in a day.

Snakes that have recently eaten rarely move any significant distance and will stay in one location, basking to optimize their body temperature until the prey item has been digested.

The blue-white colour comes from an oily secretion between the old and new skins; the snake's coloration will also look dull, as though the animal is dusty.

[6] In defence they can produce a garlic-smelling fluid from the anal glands, and feign death (thanatosis) by becoming completely limp[7] when they may also secrete blood (autohaemorrhage) from the mouth and nose.

[1] In the Baltic mythology, the grass snake (Lithuanian: žaltys, Latvian: zalktis) is seen as a sacred animal.

In spite of the serpent's symbolic meaning as a symbol of evil in Christianity, in Latvia and Lithuania there were various folk beliefs, dating even to the late 19th century, that killing grass snakes might bring grave misfortune or that an injured snake will take revenge on the offender.