When your faction takes control over a fort in any territory there is a global buff that will be rewarded to your faction. Once you lose control of that fort your faction loses the global buff. Below is a quick reference chart for the global Fort Buffs in New World. 

New World Fort Buffs Chart

Territory Faction Control Bonuses
BrightwoodCamping no longer costs resources
Brimstone SandsGathering quantity +10%
Cutlass KeysIncrease global gathering luck by 1%
Ebonscale ReachDecreases the cost of items in the faction store by 5%
EdengroveGlobal Tax Reduction -10%
EverfallIncreases the amount of Azoth Salt gained by 10%
Monarch BluffsIncreases all experience gains by 5%
MourningdaleIncrease the gear score ceiling of crafting by 5
ReekwaterIncreases the amount of PVP Experience gained by 10%
Restless ShoresAll fast travel is now free
Weaver’s FenGlobal refining yield boost of 10%
WindswardGlobal consumable bonus +10%

Along with the global buff, your faction will receive a territory-specific buff for each fort that is owned. Each fort you capture will provide you with a bonus influence of +20% and a bonus Experience of +5% in that specific territory.

To see more about open world PvP click here.