This is a case of survivorship bias. 

Your great-...-greatparents had lots of children so some survived and some of those who survived hand lots of children, and of those some had children and some survived etc. It looks like everybody's grand-...-parents had a lot of children because those who did not have lots of children do not have descendants to be curious about how many children their grand-...-parents had.

There were a lot of people who did not have children at all, and a lot who did not have children who survived, else the population of England would have quintupled every 35 years instead of doubling every 35 years (and immigration from Europe and Ireland is included in this doubling).