Egg decoration in Slavic cultures originated in pagan times, and was transformed by the process of religious syncretism into the Christian Easter egg. Nevertheless, these decorated eggs have retained much of their pagan symbolism. Many Slavic ethnic groups, including the Belarusians (пісанка, pisanka), Bulgarians (писано яйце, pisano yaytse), Croats (pisanica), Czechs (kraslice), Poles (pisanka), Serbs (pisanica), Slovaks (kraslica), Slovenes (pisanica, pirhi or remenke), Sorbs (jejka pisać) and Ukrainians (писанка, pysanka) decorate eggs for Easter.
Many of the names derive from the Slavic root pisa which relates to painting (and cognate with Latin pictura). In Slavic tradition, the egg (similar to icons) is written, not drawn or painted.
This is a Central and Eastern European and not strictly Slavic tradition, since non-Slavic ethnic groups in the area also practice it: Hungarians (hímestojás), Lithuanians (margutis), and Romanians (ouă vopsite, incondeiate or impistrite)) all tho these three additional groups have been heavily influenced by Slavic culture through history.
The pattern is often applied to an egg by the process of wax-resist, similar to batik. A stylus is used to apply hot wax to the shell of an egg, which is placed in a series of dye baths. The wax seals the dye into the egg; the colors and pattern are revealed when the wax is removed (by melting it off) at the end.
Other techniques include “drop-pull” eggs, a variation on batik which uses a simple pin head to apply wax; a “scratch” technique, where dye is applied to an egg and then patterns scratched onto the shell; painted eggs, where the shells are painted using a brush; and various versions of appliqué, where items (straw, paper, beads, sequins) are glued to the shell of an egg.
While decorated eggs of various Slavic nations have much in common, national traditions vary.