How the West Was Won

 is a gameplay achievement and a trophy in Red Dead Redemption.

Description
Reach the top rank for multiplayer experience.

Tips and Tricks
The player must participate in enough multiplayer activities and game modes and accumulate experience points to reach level 50. One of the fastest ways to accomplish this in Free Roam is by attacking Gang Hideouts. How many points earn depends on how many enemies killed (and whether or not chaining the kills). Some "XP Rich" gang hideouts include:

Please note that the Title Update 1.01' cuts down on the experience players can earn from gang hideouts.

Pike's Basin
The basin is large, but with a horse it is easy to traverse, and should be finished in under 10 minutes, and the somewhat scattered enemies can be killed relatively easily.

Twin Rocks
Due to the large amounts of enemies clustered in a relatively small and open hideout, Twin Rocks can be cleared quickly and efficiently by a single player. The clustered enemies also allows for large chain kills, further increasing the amount of XP you get. Twin Rocks can be cleared in less than 2 minutes. Two experienced players can clean it out in about 45 seconds, earning roughly 500XP apiece (assuming they get the Cleaned House bonus, which is easy with 2 people).

Tesoro Azul
Tesoro Azul is another hideout that can be cleared relatively easily (with the only possible difficulty being reinforcements throwing in Fire Bottles and firing from a distance). The hostiles inside the hideout are spaced close together, directing the fight to close quarters and alleys. In this hideout keeping the women alive will also net the player extra XP.

Double XP Weekend
Occasionally, the official Red Dead Redemption website will announce double experience points weekends, meaning that anything that gets you XP (kills, challenges, gang hideouts, etc.) will be doubled. Check the official website for any news.

Trivia

 * The name of the achievement is likely a reference to the classic western film How The West Was Won released in 1962.