A somewhat formal or academic term for a historian, often used in scholarly or journalistic contexts.
He is known as a historian of Roman history.
He is a historian specializing in Japanese history.
The historian discovered new documents.
According to historians, this event is based on a misunderstanding.
私家 (しか) means 'private household/personal' and is unrelated to history, though it shares the exact pronunciation with 史家.
詩歌 (しか) refers to poetry and verse, a completely different meaning from 史家 despite the identical reading.
Compound of 史 (history) and 家 (specialist, expert). The reading しか is the standard on'yomi combination.