The Book Of Romans is widely thought of as one of the most hard to understand biblical texts – and I would agree.
The historical record I work with, based largely on Dr Stephen Jones and Matthew McGee’s work, is this (these dates are generally universally accepted to within a year or two anyhow):
Jesus was crucified in AD 33
Establishment of Church in Rome AD 33 – 34
Stoning of Stephen and great Jerusalem persecution AD 35
Paul’s conversion AD 37
Paul’s letter to the Romans AD 57 – 58