In 1618 he was appointed physician extraordinary to the king, and, a little later, physician in ordinary.

He was in attendance upon Charles I.at the battle of Edgehill, in 1642, where, with the young Prince of Wales and the Duke of York, after seeking shelter under a hedge, he drew a book out of his pocket and, forgetful of the battle, became absorbed in study, until finally the cannon-balls from the enemy's artillery made him seek a more sheltered position.
On the fall of Charles I.he retired from practice, and lived in retirement with his brother.

He was then well along in years, but still pursued his scientific researches with the same vigor as before, directing his attention chiefly to the study of embryology.

On June 3, 1657, he was attacked by paralysis and died, in his eightieth year.

He had lived to see his theory of the circulation accepted, several years before, by all the eminent anatomists of the civilized world.
A keenness in the observation of facts, characteristic of the mind of the man, had led Harvey to doubt the truth of existing doctrines as to the phenomena of the circulation.