Anyone know of any book on the history of the early church that is accurate? (no secular nonsense)
You might consider Eusebius’ History of the Early Church. I want to say it was written near the end of the 4th century, but don’t quote me on the exact timeframe. You should be able to find a translation in any major book seller, or order it otherwise.
I second this recommendation. Eusebius died around 340 AD, so it was written before that. It covers the time from the Apostles through the Council of Nicea (325 AD).
The full text is also online in several places. Here it is at New Advent:
If you’re looking for a readable contemporary Church History without the secular nonsense, I’ve heard great things about H.W. Crocker’s Triumph.