I thought enclosure in England started in the late Middle ages - around the 13th century
From Wikipedia:
Before the 17th century enclosures were generally by informal agreement. When they first introduced enclosure by Act of Parliament the informal method continued too. The first enclosure by Act of Parliament was in 1604 and was for Radipole, Dorset. This was followed by many more parliamentary Acts and by the 1750s the parliamentary system became the more usual method.
There were a lot of factors. New crops from the New World, new technology, etc. Large landowners were able to maximize their incomes by depriving commoners access to what had traditionally been common lands. That led to fewer agricultural opportunities for peasants and subsequent growth in non-agricultural work.
Although the number of agricultural workers declined, food production increased, populations increased, and this greatly facilitated the subsequent Industrial Revolution as both production and consumption grew.