You had to be baptised to receive Communion, so this is why, sometimes, people got baptised before their wedding.
The Book of Common Prayer, has this comment: "It is convenient that the new-married persons should receive the holy Communion at the time of their Marriage, or at the first opportunity after their Marriage."
Adult baptism was quite common. There has always been a service in the Book of Common Prayer for the "Baptism of Those of Riper Years"
Stan