Looking for an arcane historical fact to represent this date I found that Grandfather Opechancanough opened the Third Powhatan War on the Jamestown settlers on March 18, 1644. It was in this raid that Grandfather John Woodson was slain.
I have touched on this incident in a couple of earlier posts.
Historic Jamestowne National Park Service
String Too Short to Tie here and here.
Wikipedia Anglo-Powhatan Wars