Some authors, notably Robert Service, have claimed that Trotsky's childhood first name was the Yiddish "Leiba". The American Trotskyist David North said that this was an assumption based on Trotsky's Jewish birth, but, contrary to Service's claims, there is no documentary evidence to support his using a Yiddish name, when that language was not spoken by his family. Both North and political historian Walter Laqueur wrote that Trotsky's childhood name was "Lyova", a standard Russian diminutive of the name "Lev." North has compared the speculation on Trotsky's given name to the undue emphasis given to his having a Jewish surname.