When Portus was built in the middle of the first century AD, the dead were always cremated in so called public ustrinae.
This custom continued till the reign of the emperor Hadrian (117 AD) when burial was introduced and for a long time cremation and inhumation went side by side.
At the end of the second century burial was more common than cremation and after the
early third century it seems that no new provisions for cremation were made.
It is not clear why these customs changed. Christianity was not yet that popular and there is no evidence of a growing spritual respect for the human body.
It probably was just a new fashion.
The first person known to have adopted this new fashion at Rome was a certain Abascantus, secretary of the emperor Domitian. The Roman poet Statius wrote that
Abascantus embalmed his wife's body after her death with costly ingredients.
Statius suggested that he chose for burial because he found cremation too crude.
Anyhow, we shall see that the change of custom
had its influence on the burial culture.