King James VI of Scotland was crowned King James I of England and Ireland.
James’ mother was Mary, Queen of Scots, who gave up the Scottish throne to allow him to rule from the young age of thirteen months. James was also the great-great-grandson of King Henry VII, so when Elizabeth I died in 1603 with no rightful heirs, the throne of England and Ireland was left to James. When he became King James of England and Ireland, he remained as King of Scotland, uniting the three nations.