The base for all male dress ensembles was the shirt, "sorochka," (also called "srochka", "scrachitsa", etc).
The Russian word for a shirt (rubaha - roo-BAH-khah)
is derived from ancient Slavic word rub - rOOb - a piece of cloth.
For many centuries a shirt was the main clothing for both noble people and peasants.
Rubakha was common until the 20th century.
The rubakha was a straight garment, sometimes with panels sewn in on the bottom part to make it easier to walk in.
Sometimes it had a very high neckline, in which case there would be a slit in the front fastened with a button.
More like a night dress, it extended to the knees.
Peasants made rubakhas out of cheap linen, with strips of red cloth around the neckline for decoration.
The wealthier class donned rubakhas of finer linen, with special embroidery revealing their status.
Buttons were made out of either bone or wood. These were almost always white.
It was considered indecent to wear the rubakha without a belt.
The top of the rubakha would be pulled over the belt so as to not emphasize the waistline.
The Design of Embroidery:
In Slavic tradition, crosses (both X-like and + -like ones) symbolized Fire.
X-cross was used for Heavenly Fire (Sun, thunderbolt).
Russian peasants called an X-like cross as ognevets ("caused by fire and closely related to it").
+ - like cross depicted Earthly Fire.
Being a sibling of Sun and Thunderstorm,
it shared the Sun's ability to produce a plentiful harvest, abundance, and wealth.
Floral X-crosses - Green Fire,
+s - a ritual fire,
and a zig-zag border - a sign for water.
Life, Tree, Fire and Water.
A man's shirt must carry talismans around a neck, wrists, and at the bottom.
At least, it should be a red "fire-line".
Embroidered or appliqued sacred designs worked much better.
Kosovorotka is a traditional Russian men’s shirt with a collar that fastens on one side (usually – on the left)
instead of the more common central position.
It first appeared in Russia around the 12th century.
Academician Dmitry Likhachev explains that the design in that
“a lateral slit has to prevent the crucifix worn around one's neck from coming out during work.”