The Cyrillization of Polish has been practised in many forms and began in the mid-19th century in the Russian Empire. Between 1772 and 1815, the Russian Empire seized about four fifths of Poland-Lithuania, where Polish was the leading official language. Polish remained the official language of the incorporated Polish-Lithuanian territories until the late 1830s. Later, it was gradually replaced with Russian through the mid-1860s. A middle stage for the transition was the use of the Russian-style Cyrillic for writing Polish.

Russian Cyrillization of Polish 

The system of the Cyrillization of Polish, as employed in today's Russia, emerged during the 1970s in the postwar Soviet Union. It is a form of transcription.

New Polish Cyrillic 

Since the early 1990s Polish-language religious books produced for Catholics in western Belarus (i.e. Grodno Diocese) have been published in the newly-devised Polish Cyrillic, which is largely based on the Russian form of this alphabet.

The Lord's Prayer 
In Polish Cyrillic:

In the Polish Latin alphabet:

References 

Polish
Polish language