Brumbelow
It is probably a variant of English Rumbelow, itself of uncertain origin; most likely a habitational name from a place in Aston, Birmingham, called the Rumbelow, from a misdivision of the Old English locative phrase æt þæm þreowan hlawum ‘at the three hills’. The Old English word hlaw meant ‘small hill’ or ‘tumulus’.
Alternatively, it may be an Americanized form of the German habitational name Brummerloh, from a place so named near Varel, Lower Saxony.
from Dictionary of American Family Names, Oxford University Press