Complex sentence: In 1639, the college was renamed "Harvard College" after clergyman John Harvard, an alumnus of the University of Cambridge who had willed school £779 pounds sterling and (perhaps more importantly) his library of some 400 books.
Split into simpler sentences: In 1639, the college was renamed "Harvard College" after deceased clergyman John Harvard, who was an alumnus of the University of Cambridge. He had left the school £779 pounds sterling and his library of some 400 books.