First novel to reach over 1 million copies sold
Others claim that Cervantes' Don Quixote was the first book to sell 1 million copies. Considering projections and longevity as benchmarks, perhaps it was. Yet, Don Quixote was initially released in two volumes as two distinct books with some shared characters. Ten years separated the publication of the two volumes, with the second acting more as a continuation of the first.
It was also frequently revised and condensed for publication; this was typically due to bad translations. Today, there are more than 20 English translations available, with varied degrees of accuracy. Both young adult and children's editions are available. Don Quixote is essentially what we would refer to as a franchise today.
Uncle Tom's Cabin, originally serialized and eventually released in book form in 1852, is widely regarded as the first American novel to sell 1 million copies. In its first year, it sold 300,000 copies in the United States and another 200,000 when it was published in Great Britain. It had sold 1.5 million copies in Britain by the time Lincoln took office, a major portion of them being pirated.
At the start of the Civil War in 1861, sales in the US were declining. But, once the war started, both in the Union and among the military, sales soared. It rose to become the second best-selling book and best-selling novel in the world throughout the 19th century and was published in all significant languages.