Walter Parkin was a wizarding butcher in the 1400s. In 1422, his seven children - four sons and three daughters - formed the Wigtown Wanderers Quidditch team. Walter often attended matches holding his wand in one hand, and a meat cleaver in the other. Opposing teams were often intimidated by his presence on the sidelines.
The name "Walter" comes from a Germanic name meaning "ruler of the army", composed of the elements wald "rule" and hari "army". The Normans brought it to England, where it replaced the Old English cognate Wealdhere. A famous bearer of the name was Sir Walter Scott (1771-1832), a Scottish novelist who wrote 'Ivanhoe' and other notable works.
"Ruler of the Army" probably being a reference to the "army of children" that made up the Wigtown Wanders team.