The first three Terminator stories, The Terminator, Terminator 2: Judgment Day and Terminator 3: Rise of the Machines describe a timeline bracketed by two events: the arrival in 1984 of a Terminator from the future and the act of Kate Brewster-Connor sending a reprogrammed Terminator back to 2004 from some year in the future.
This document is an attempt to describe all of the events that occur during this period in a single unbroken timeline free of inconsistencies, paradoxes or circular causality.
We will begin with some initial assumptions and define guidelines as to what can or cannot happen. We will explain the methods we employ to achieve this.
We have not attempted to incorporate the television series, Terminator: The Sarah Connor Chronicles, the fourth movie, Terminator: Salvation, the fifth movie, Terminator: Genisys nor the sixth movie, Terminator: Dark Fate, into this document.
The main reason for the exclusion of the TV show is that it simply does not fit. The Chronicles begins by taking John and Sarah out of the sequence between Judgment Day and Rise of the Machines. The events that occur after this removal cannot be reconciled with the first three stories and really represent separate and alternate timelines.
The reason that Salvation has not been included is that it contains no time travel at all.
Genisys, although it contains much time travel, is not included as it contains fatal flaws with respect to time travel. It cannot be reconciled with itself let alone with the other movies. We discuss these flaws in detail in the Genisys review.
Finally Dark Fate. Not sure, might do.