Sienkiewicz is a Polish form of the Belarusian surname Siankievič.Унбегаун Б. Русские фамилии / Пер. с англ. Общ. ред. Б. А. Успенского. — М.: Прогресс, 1989. — C. 232. — . Russian equivalent: Senkevich.

Notable people with the surname include:

Agnieszka Sienkiewicz (born 1984), Polish actress Bartłomiej Sienkiewicz (born 1961), Polish politician Bartosz Sienkiewicz (born 2001), Polish para-athlete Bill Sienkiewicz (born 1958), American artist Henryk Sienkiewicz (1846–1916), Polish journalist and writer Ruth Sienkiewicz-Mercer (1950–1998), American activist

See also Sinkiewicz

References