A pogrom is a violent riot incited with the aim of massacring or expelling an ethnic or religious group, particularly Jews. The term entered the English language from Russian to describe 19th- and 20th-century attacks on Jews in the Russian Empire. Similar attacks against Jews which also occurred at other times and places became known retrospectively as pogroms. Sometimes the word is used to describe publicly sanctioned purgative attacks against non-Jewish groups. The characteristics of a pogrom vary widely, depending on the specific incident, at times leading to, or culminating in, massacres.