According to this definition, the Great Apostasy resulted in the removal of the authority of the priesthood from the Earth, the loss of a living prophet to lead the body of believers, and thus the loss of the Church on Earth. Hence, the need for a restoration under the prophethood of Joseph Smith.
This article on the LDS website states that the Great Apostasy occurred around the end of the 1st century AD, when the last apostle passed away.
My question is, what does this mean for the church that the LDS scriptures teach that Jesus founded in the Americas and which lasted for a much longer time? How could the Great Apostasy have occurred if there was a prophet on the Earth and a church with the authority of the priesthood?
This Wikipedia article provides a timeline for the Book of Mormon events: en.wikipedia.org/wiki/Book_of_Mormon_chronology#Between_AD_36_and_321
Assuming the dates are correct, the Church in the Book of Mormon lands experienced a good deal of unity and peace until the very end of the second century and then only very gradually fell into apostasy. There was a prophet, priesthood, presumably a church, on Earth until the 400s AD.
How can the LDS understanding of the Great Apostasy and its first century date fit with the LDS belief in the historicity of the Book of Mormon?