Yes, it was. And yet, in the sixteenth century, Rome [re-embraced semi-Pelagianism](
https://www.modernreformation.org/resources/articles/the-pelagian-captivity-of-the-church). And the Reformers rightly protested.
> Ironically, the Church condemned semi-Pelagianism as vehemently as it had condemned original Pelagianism. Yet by the time you get to the sixteenth century and you read the [Roman] Catholic understanding of what happens in salvation the [Roman] Church basically repudiated what Augustine taught and Aquinas taught as well. The [Roman] Church concluded that there still remains this freedom that is intact in the human will and that man must cooperate with-and assent to-the prevenient grace that is offered to them by God. If we exercise that will, if we exercise a cooperation with whatever powers we have left, we will be saved. And so in the sixteenth century the [Roman] Church reembraced semi-Pelagianism.
-- R. C. Sproul, "[The Pelagian Captivity of the Church](
https://www.modernreformation.org/resources/articles/the-pelagian-captivity-of-the-church)"