Brand was the captain of the Harriers when they played what has been termed “the finest match ever seen” – an exciting seven-day marathon against the Holyhead Harpies in 1953. At the end of the match, he immediately proposed marriage to Gwendolyn Morgan, the Captain of the Harpies (she hit him with her Cleansweep 5) (QA7).
Stamina to survive a seven-day long match, a bit impulsive and romantic.
Rudolf derives from the Germanic name Hrodulf (hrod "fame", wulf "wolf") (Behind the Name).
The surname Brand can derive from several sources, including the Germanic given name Brando ("sword") or Anglo-Saxon brinnan ("flash, lightning") (Internet Surname Database).
From the Web
WizardingWorld.com (Pottermore) features:
Harry Potter Wiki: Rudolf Brand