James was the son of Mary, Queen of Scots, and a great-great-grandson of Henry VII, King of England and Lord of Ireland, and thus a potential successor to all three thrones. He succeeded to the Scottish throne at the age of thirteen months, after his mother was compelled to abdicate in his favour. Four different regents governed during his minority, which ended officially in 1578, though he did not gain full control of his government until 1583. In 1603, he succeeded the last Tudor monarch of England and Ireland, Elizabeth I, who died childless. He continued to reign in all three kingdoms for 22 years, a period known as the Jacobean era, until his death. After the Union of the Crowns, he based himself in England (the largest of the three realms) from 1603, returning to Scotland only once, in 1617, and styled himself "King of Great Britain and Ireland". He was a major advocate of a single parliament for England and Scotland. In his reign, the Plantation of Ulster and English colonisation of the Americas began.