The origin of the given name Gilman is derived from Hebrew, meaning 'reward' or 'protection'. It is a variant form of Gilbert, which was introduced into England by the Normans in the 11th century and has since been used as both a given name and a surname.
"Gilman appears to have been quite popular around the turn of the century, with significant fluctuations in birth rates thereafter. The peak occurred during World War I, suggesting potential patriotic naming trends."