There is nothing that must be fulfilled before the return of Jesus Christ. Jesus’ Second Coming could be at any time and will be without any warning.
Many have asserted that a great apostasy must first occur and the antichrist must also be revealed, before the return of the Lord Jesus. But to maintain such a position renders the immediacy of Jesus’ return as misleading. If the nation of Israel must be converted first, the antichrist revealed, and if any number of other things must occur first, then the immediate return of Jesus Christ is not a possibility for the present. To maintain that certain things must occur first undermines any sense of urgency that should be felt.
As a moderate Preterist, I believe that certain prophecies have been fulfilled around the events of AD 70, when Rome sacked Jerusalem. The only literal prophecies to be fulfilled are Jesus’ return, the resurrection of the dead, and the great judgment.