The Eurasian wren occurs in Europe and across the Palearctic – including a belt of Asia from northern Iran and Afghanistan across to Japan.

The scientific name is taken from the Greek word "troglodytes" (from τρώγλη troglē "hole", and δῠ́ειν dyein, "creep"), meaning "hole-dweller", and refers to its habit of disappearing into cavities or crevices whilst hunting arthropods or to roost.

[4][5] The Eurasian wren was described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Motacilla troglodytes.

[7] In 1555 the German naturalist Conrad Gessner had used the Latin name Passer troglodyte for the Eurasian wren in his Historiae animalium.

[8] The species is now placed in the genus Troglodytes that was introduced by the French ornithologist Louis Pierre Vieillot in 1809.

[10] The disputed subspecies T. t. orii, the Daito wren, became extinct around 1940 – if it was indeed a valid taxon and not merely based on an anomaly.

[17] The Eurasian wren is a plump, sturdy bird with rounded wings and a short tail, which is usually held cocked up.

The most common call is a sharp, repeated "tic-tic-tic", similar but faster and with less isolated notes compared to that of a robin.

Despite its generally mouse-like behaviour, the male may sing from an exposed low perch as its whole body quivers from the effort.

[17] It occupies a great variety of habitats, typically any kind of cultivated or uncultivated area with bushes and low ground cover; gardens, hedgerows, thickets, plantations, woodland and reed beds.

It inhabits more open locations with clumps of brambles or gorse, rough pasture, moorland, boulder-strewn slopes, rocky coasts and sea cliffs.

[17] The wren is an ever-active bird, constantly on the move foraging for insects, in the open or among thick vegetation.

It moves with quick jerks, probing into crevices, examining old masonry, hopping onto fallen logs and delving down among them.

Occasionally it flits away, its short flights swift and direct but not sustained, its tiny round wings whirring as it flies.

It is mouse-like, easily lost sight of when it is hunting for food, but is found everywhere from the tops of the highest moors to the sea coast.

Although it is an insectivore, it can remain in moderately cold and even snowy climates by foraging for insects on substrates such as bark and fallen logs.

[17] The neatly-domed nest has a side entrance and is built of grass, moss, lichen and dead leaves, whatever is available locally.

The wren also features in the legend of Saint Stephen, the first Christian martyr, who supposedly was betrayed by the noisy bird as he attempted to hide from his enemies.

[30] The tradition, and the significance of the wren as a symbol and sacrifice of the old year, is discussed in Sir James Frazer's The Golden Bough.

With a conspicuous sprig of laurel clamped in its beak, the wren flew desperately into the Roman Senate, but there its pursuers overtook it and tore it to pieces.