Complex sentence: The pamphlet was an instant hit and was reprinted 14 times in 1518 alone, in print runs of at least 1,000 copies each time, and is regarded by many as the true starting point of the Reformation.
Split into simpler sentences: The pamphlet was an instant hit and was reprinted 14 times in 1518 alone, in print runs of at least 1,000 copies. It is regarded by many as the true starting point of the Reformation.