Revelation 7 and the seals.

In Rev. 7 John sees a great multitude wearing white robes standing around the throne as if they had instantly appeared out of no
where. This is different that the
martyrs in chapter 5 who are under the altar. This multitude is wearing their robes. John exclaims, who are these people and where did they come from? The elder answers from out
of the Great Tribulation. Isn't this when the rapture takes place, between seals 6 and 7?

The first seal is the Anti Christ riding in. He is the cause of seals 2-5, where 5 is the death of martyrs. If God is the one causing the action of the seals, then that means he is responsible directly for the death of the martyrs in seal 5, no? Wouldn't this put the rapture after the start of the tribulation? Please provide Scripture and references supporting or refuting this pre wrath view of the rapture. I have always been pre trib, but my friend brought up the above point.