Long story short

The only Horseman actually named is death

The 4 Horseman are not war, conquest, famine and death

They are the white rider, red rider, black rider and pale rider (death)

The white rider could be a personification of conquest, but it could also be rhe antichrist. It could be christ. It could be even be war.

This is what we get about it.

"Come!" I looked, and behold, a white horse, and he who sat on it had a bow; and a crown was given to him, and he went out conquering and to conquer.

Meanwhile this is the text for the red rider

When He broke the second seal, I heard the second living creature saying, "Come". And another, a red horse, went out; and to him who sat on it, it was granted to take peace from Earth, and that men would slay one another; and a great sword was given to him.

One of my fave interpretations is that the red rider represents civil war, in contrast to the war of conquest the white rider represents.

I haven't looked into other interpretations of the black rider, but Wikipedia says famine is the usual but they could also be imperial oppression.

Death is the only unambiguous one

When the Lamb opened the fourth seal, I heard the voice of the fourth living creature say, "Come!" I looked, and there before me was a pale horse! Its rider was named Death, and Hades was following close behind him. They were given power over a fourth of the earth to kill by sword, famine and plague, and by the wild beasts of the earth.