It’s not usually s surname, it’s an occupation or title.
Historical definitions include:
HISTORICAL
a man holding and cultivating a small landed estate; a freeholder.
HISTORICAL
a servant in a royal or noble household, ranking between a sergeant and a groom or a squire and a page.
A yeoman was a farmer who owned and worked his own land — not to be confused with "yo, man!" Although experts aren't entirely sure of the origin of yeoman, they speculate that it is a shortened version of young man. Yeoman is now just a historic term and it is unlikely to be used to describe a landowning farmer today.
I see people describe themselves as “yeoman” in wills in Colonial America and Tudor era England.
