Mecislaus is an ancient and distinctive given name of Slavic origin, derived from the Slavic elements 'miec' meaning 'who?' and 'slav' meaning 'glory'. This name was particularly popular in the early Middle Ages among the Slavic tribes that inhabited present-day Poland and Bohemia. It is often associated with Mecislaus I, Duke of Bohemia from 1031 to 1033, who played a significant role in the history of the region during his reign.
"In 1920 alone, five babies were named Mecislaus."