English people started settling in parts of America, especially Virginia, as early as 1607. Many of these were largely motivated by the hope of finding wealth, adventure and other opportunities, in this still unexploited continent. They knew from Elizabethan explorers such as Sir Walter Raleigh that America contained huge potential wealth. Many of the most successful settlers would become the owners of Virginia tobacco plantations (and, in most cases, the slaves that worked them.)
However, the most famous group of English settlers were undoubtedly the "Pilgrim Fathers" who sailed for New England on the Mayflower in 1620. In fact less than half of these could really be considered pilgrims in a religious sense, but the search for religious freedom made up the biggest single motive for leaving England. At that time the Puritans, as this group of ultra-strict Protestants were known, were not allowed to worship as they thought fit, and were often persecuted. They wished to found a "perfect city" like the Biblical Jerusalem, and to live according to (their interpretation of) strict Biblical teaching, as well as to escape persecution.
Religious persecution was a strong factor in the emigration of many people in the early years.
Poor living conditions in England and Wales also played a big part in the decision to go.
The rule of Oliver Cromwell in the 1600's also saw the White slave movement. Cromwell was very harsh with anyone who opposed him and punished many English , Scots and Irish rebels by shipping them to the colonies to enslavement on the plantations. He used the man and woman power of the rebels to work the plantations under harsh conditions.
The use of these people in the White Slave trade is not well known though there is good documentary evidence for it. The Western Rebellion in the areas around Devon, Bristol and Cornwall lead to many of the defeated 'rebels' being shipped as slaves to the colonies. the Irish suffered very badly under Cromwell to and the Scots to a lesser degree.