Basics: The two factions are at war with each other over Soulstones and you must choose a side to fight for.

Soulstone Plains: Level 50 area where you will participate in a half pve, half pvp combat system while wearing your faction uniform and hopefully to obtain soulstones by completing the dailies. However, if you do not have enough AP (Attack Power) you will probably not be able to complete these dailies. In fact, you will want to at least obtain True Pirate weapon (maybe even True Siren accessories) before bothering to attempt Soulstone Plains. (500 AP to be on the safe side.)

Faction Insignias: As you complete faction dailies you will obtain Faction Insignias, which only use is to donate to your Clan for crafting and ranking the Clan. If you are not in a Clan then these insignias are useless and will only take up space, so best bet is to trash them or join a Clan as soon as possible so they don't take up space.

Extras: If you farm the insignias in designated areas around the map, consisting of their own faction camps, you will be able to use those insignias on the faction merchants in that area to buy extra items like costumes. You cannot use those insignias on any other merchants except the ones in that area. For example: Misty Woods Insignias can only be used at your faction merchants in Misty Woods. Scorching Sand Insignias can only be used at the faction merchants in Scorching Sands. Same goes for obtaining these insignias, only from farming the faction captains of the named area. (Misty Woods captains, Scorching Sand captains, etc...)

Important: To obtain Misty Woods Cold Iron breakthrough weapon for upgrading you will need to have Squire faction ranking, and buy it from the Misty Woods faction merchants. Be sure to do enough dailies to at least be able to buy this weapon or you will not be able to progress your weapon any further.