Her life has been celebrated in song, story and a Disney cartoon, but no one knew where Pocahontas tied the knot with a tobacco farmer—until now.

Archaeologist Bill Kelso and his team were digging this summer in a previously unexplored section of the fort at Jamestown, Va., the country's oldest permanent English colony, when they uncovered a series of deep holes. They believe the holes once anchored heavy, timber columns supporting the fort's first church, known to have been built in 1608 and the place...