Complex sentence: In the decades after the war interest in the affair was revived from time to time, beginning in 1963 when Blythe, deemed by Parris to be the affair's "best historian", first published his account.
Split into simpler sentences: In the decades after the war interest in the affair was periodically revived. In 1963 Blythe, deemed by Parris to be the affair's "best historian", published his account.