Son of William
An English patronymic surname meaning 'son of William'. The root name William is derived from the Germanic elements 'wil' (will or desire) and 'helm' (helmet or protection).
Less common today
Williamson isn't in the latest US Top 1000. It last peaked at #7,978 in 1995.
US births per 5-year period, 1990–present (SSA data).
Prominent military historian and professor
A minor wizarding official at the Ministry of Magic · Harry Potter and the Order of the Phoenix
