Wikipedia
Ijsbrand is a Dutch male given name of late Old Dutch or early Middle Dutch origins. The first syllable, "eis" (or ijs/ys), is derived from the ancient west Germanic word for iron. The second syllable, "brand" (or brandt), traditionally meant fire but was also used for things made in fire, such as a sword. The NRC birth registry thus suggests the meaning "iron sword".
The name is at least as old as the 12th century, when it was a distinguished name for the Lords of Haarlem. After it had caught on as a common given name, Ijsbrand remained popular throughout Dutch history and up to the present day.
According to the figures of the Sociale Verzekeringsbank, the organization that implements national insurance schemes in the Netherlands, the year 2009 saw the name IJsbrand given to 4 newborn boys in The Netherlands, in the same year the alternative spelling Ysbrand had a count of 5.