A burka is a dress made from felt

Felt

Felt is a non-woven cloth that is produced by matting, condensing and pressing woollen fibres. While some types of felt are very soft, some are tough enough to form construction materials. Felt can be of any colour, and made into any shape or size....

 or karakul (the short curly fur of young lambs of the breed of that name). Karakul being quite expensive, burkas were usually sewn from felt treated to look like karakul. Burkas are sewn with high, squared off shoulders, and wearers will have a distinctive high-shouldered silhouette.

Burkas were part of the customary male garb of various peoples inhabiting the Caucasus

Caucasus

The Caucasus, also Caucas or Caucasia , is a geopolitical region at the border of Europe and Asia, and situated between the Black and the Caspian sea...

 region. Burkas were adopted by Russian cavalry, and worn as part of the Russian military uniform from the middle of the 18th century until the 1850s, during the Caucasus War.
Vasily Chapayev

Vasily Chapayev

Vasily Ivanovich Chapayev or Chapaev was a celebrated Russian soldier and Red Army commander during the Russian Civil War.-Biography:...

 wore a burka as a part of his military uniform

Military uniform

Military uniforms comprises standardised dress worn by members of the armed forces and paramilitaries of various nations. Military dress and military styles have gone through great changes over the centuries from colourful and elaborate to extremely utilitarian...

.