Resistance (Terminator)

With the date of Judgment Day changing, no date can be set to when the Resistance started. Though it can be inferred that it started soon after Judgment Day took place.

In the Terminator Salvation timeline, it can be said that the Resistance was founded from the remnants of the world's military forces, who's surviving officers lead from a Los Angeles class submarine in the form of a leading council of Generals and Admirals, with General Ashdown leading them. Sometime after the destruction of the Resistance Headquarters and Skynet Central, it can be assumed that John Connor, the commander of Tech-Com, has taken control of the Resistance. As stated by Kyle Reese, the Resistance triumphed over Skynet, and in a last ditch effort the computer system sent back a Terminator to kill Sarah Connor. (Source: Terminator wiki)