Free Horses in Red Dead Redemption 2 

War horse: (RDR 2 standard edition) Redeem code on back of card.

War horse (standard edition): Visit valentine stables.

The breed is Ardennes.

You have to buy free and name it war horse.

Check Ardennes stats.

And test ride Ardennes war horse.

Thoroughbred: (RDR 2 special edition) Redeem code on back of card.

Thoroughbred(special edition): You have to visit Valentine stables.

The breed is Thoroughbred.

You need to buy free and name it special edition.

Check Thoroughbred stats.

After that, test ride Thoroughbred.

Then you have to go to Barrow Lagoon and save a new slot.

Travel to this spot near Lake Isabella.

You will see a white horse.

Now you have to crouch and walk slowly towards horse.

Horse will be lost forever if it runs too far.

If the horse is lost, you need to reload the previous save.

Hold the L2 button and press square near horse.

Repeat while crouching, moving toward horse.

You can mount a horse with a triangle button.

Move left analog down left or right.

You have to repeat if knocked off horse.

You will be able to tame it eventually.

You can transfer the saddle (L2+up button).

Ask your other horse to follow you.

After that, go back to a stable.

Pat/Feed/Brush horse to increase bond.

Original free game horse (all edition): Tennessee walker breed (5 speed 4 acceleration).

Redeemable war horse (standard edition): Ardennes breed (6 speed 5 acceleration).

Redeemable Thoroughbred (special edition): Thoroughbred breed (10 speed 7 acceleration).

Free roaming best horse (all editions): Arabian breed (9 speed 8 acceleration).

Customizing the most expensive upgrades: Saddle.

Customizing the most expensive upgrades: Mane.

Customizing the most expensive upgrades: Tail.

Customizing the most expensive upgrades: Grooming.

Rename horse free Arabian.

Now you can ride the best horse with the best customizations.