1897 Russian Census in Poland
In the years between 1795-1918, a great part of Poland was under control of the Russian Empire. In 1897, the First National Census of the Russian Empire was performed in that area. Each household was listed with the names of all residents, parents and children.
Unfortunately, the lists of households were destroyed for the Polish area and only statistical summaries survived. As a result, this kind of record should not be considered as a resource for Polish genealogy.
Possibly some records from that census survived for Łomża city and nearby villages.
More information can be found HERE.