Apparently all the U.S. Cronkrites are descended from a Dutchman named Harck (or Herk) Syboutszen. He lived in what is now the New York City area, back in the 1600's.
Based on his name, he was ethically Frisian. He worked as a ships carpenter and sometimes worked for the Dutch West India Company of Amsterdam. He sold his house on Manhattan Island for 175 guilders and half a barrel of beer.
At some point, 4 of his sons adopted the surname Kranckheyt. Since that time, at least 43 variations of this name have appeared, including our own Cronkrite.
[source - unverified]