Wilhelmus (William, Willem) Beekman was born at Hasselt, Overijssel, Netherlands on April 28, 1623 to Hendrick Beekman and Mary Baudartius, who had married in 1621 at Zutphen, the Netherlands.
His maternal grandfather, theologian Willem Baudartius, was one of Dutch Calvinism's most zealously orthodox protagonists [REF].