Why was Sir Walter Raleigh imprisoned by King James?

A favorite of Queen Elizabeth I, Sir Walter Raleigh was distrusted by Elizabeth's successor, King James I. In 1603, Raleigh was accused of plotting against James I, and he was stripped of all his offices and imprisoned in the Tower of London, where he remained for some 13 years. In 1616, he was released and returned to Guyana, where he unsuccessfully searched for gold. While there, his men captured and burned a Spanish settlement. The Spanish ambassador to England demanded punishment. James I, happy to punish the man he considered an enemy, re-arrested Raleigh, charging him with treason. Sir Walter Raleigh was beheaded on October 29, 1618.