Using a premade campaign world has various advantages:

1. When the background material is known and published, you can assume that all players are familiar with the setting. Character knowledge which should be known to anyone living in that world (like basic geography, major factions and deities) doesn't have to be infodumped. This also avoids any misconceptions between you and your players about the setting. When there is any confusion, you can just read it up in the book.
2. The campaign world is written and proof-read by professional authors and playtested by countless people. This ensures that the campaign setting works and has no major logical errors.
3. It saves you a lot of work. Sure, maybe you enjoy designing your own campaign world from the ground up. But this is an activity only for your own benefit. Your players just want to play the game already. The time you spend on designing the big picture of the campaign setting is time you could spend preparing the more detailed material for the session itself (or playing).

Also, just because you are placing your campaign in an existing setting doesn't mean that there isn't room for your own creativity:

• Factions: The campaign setting might describe the major factions with world-wide influence, but that doesn't mean that there aren't any local factions which aren't powerful enough to influence world politics but are very important for what happens in a city or smaller region. So you can make up your own tribes, cults, warlords, guilds, secret societies or other small but interesting groups of people.
• Locations: Most campaign settings only describe a few major locations and leave large parts of the world only vaguely described. That leaves you a lot of room for coming up with interesting locations to populate these areas with.
• Deities: This might vary from setting to setting, but the cosmology of some of them allows lesser deities to coexist with the major pantheon of gods. They might not be as powerful and might not have as many followers, but they can still be important enough for a plot or two.
• NPCs: Most campaign settings only describe a few celebrity characters. Sometimes they even provide detailed character sheets for them. But be honest: It isn't very likely that your party of adventurers will only interact with these people. There are millions of people in the world for your players to meet, and it is your job to come up with unique personalities, backgrounds and (if necessary) character stats for them.

But remember that your players said that they want to play a specific campaign world and they expect you to deliver. Make sure your own creations do not completely overshadow the material from the setting. When you promise them Greyhawk and then give them nothing from the setting and only feed them your own stuff instead, they will feel cheated. So make sure you find a healthy mix of the official material and your own material.

Using a premade campaign world has various advantages:

1. When the background material is known and published, you can assume that all players are familiar with the setting. Character knowledge which should be known to anyone living in that world (like basic geography, major factions and deities) doesn't have to be infodumped. This also avoids any misconceptions between you and your players about the setting. When there is any confusion, you can just read it up in the book.
2. The campaign world is written and proof-read by professional authors and playtested by countless people. This ensures that the campaign setting works and has no major logical errors.
3. It saves you a lot of work. Sure, maybe you enjoy designing your own campaign world from the ground up. But this is an activity only for your own benefit. Your players just want to play the game already. The time you spend on designing the big picture of the campaign setting is time you could spend preparing the more detailed material for the session itself (or playing).

Also, just because you are placing your campaign in an existing setting doesn't mean that there isn't room for your own creativity:

• Factions: The campaign setting might describe the major factions with world-wide influence, but that doesn't mean that there aren't any local factions which aren't powerful enough to influence world politics but are very important for what happens in a city or smaller region. So you can make up your own tribes, cults, warbands, guilds, secret societies or other small but interesting groups of people.
• Locations: Most campaign settings only describe a few major locations and leave large parts of the world only vaguely described. That leaves you a lot of room for coming up with interesting locations to populate these areas with.
• Deities: This might vary from setting to setting, but the cosmology of some of them allows lesser deities to coexist with the major pantheon of gods. They might not be as powerful and might not have as many followers, but they can still be important enough for a plot or two.
• NPCs: Most campaign settings only describe a few celebrity characters. Sometimes they even provide detailed character sheets for them. But be honest: It isn't very likely that your party of adventurers will only interact with these people. There are millions of people in the world for your players to meet, and it is your job to come up with unique personalities, backgrounds and (if necessary) character stats for them.

But remember that your players said that they want to play a specific campaign world and they expect you to deliver. Make sure your own creations do not completely overshadow the material from the setting. When you promise them Greyhawk and then give them nothing from the setting and only feed them your own stuff instead, they will feel cheated. So make sure you find a healthy mix of the official material and your own material.

Using a premade campaign world has various advantages:

1. When the background material is known and published, you can assume that all players are familiar with the setting. Character knowledge which should be known to anyone living in that world (like basic geography, major factions and deities) doesn't have to be infodumped. This also avoids any misconceptions between you and your players about the setting. When there is any confusion, you can just read it up in the book.
2. The campaign world is written and proof-read by professional authors and playtested by countless people. This ensures that the campaign setting works and has no major logical errors.
3. It saves you a lot of work. Sure, maybe you enjoy designing your own campaign world from the ground up. But this is an activity only for your own benefit. Your players just want to play the game already. The time you spend on designing the big picture of the campaign setting is time you could spend preparing the more detailed material for the session itself (or playing).

Also, just because you are placing your campaign in an existing setting doesn't mean that there isn't room for your own creativity:

• Factions: The campaign setting might describe the major factions with world-wide influence, but that doesn't mean that there aren't any local factions which aren't powerful enough to influence world politics but are very important for what happens in a city or smaller region. So you can make up your own tribes, cults, warlords, guilds, secret societies or other small but interesting groups of people.
• Locations: Most campaign settings only describe a few major locations and leave large parts of the world only vaguely described. That leaves you a lot of room for coming up with interesting locations to populate these areas with.
• Deities: This might vary from setting to setting, but the cosmology of some of them allows lesser deities to coexist with the major pantheon of gods. They might not be as powerful and might not have as many followers, but they can still be important enough for a plot or two.

But remember that your players said that they want to play a specific campaign world and they expect you to deliver. Make sure your own creations do not completely overshadow the material from the setting. When you promise them Greyhawk and then give them nothing from the setting and only feed them your own stuff instead, they will feel cheated. So make sure you find a healthy mix of the official material and your own material.

Using a premade campaign world has various advantages:

1. When the background material is known and published, you can assume that all players are familiar with the setting. Character knowledge which should be known to anyone living in that world (like basic geography, major factions and deities) doesn't have to be infodumped. This also avoids any misconceptions between you and your players about the setting. When there is any confusion, you can just read it up in the book.
2. The campaign world is written and proof-read by professional authors and playtested by countless people. This ensures that the campaign setting works and has no major logical errors.
3. It saves you a lot of work. Sure, maybe you enjoy designing your own campaign world from the ground up. But this is an activity only for your own benefit. Your players just want to play the game already. The time you spend on designing the big picture of the campaign setting is time you could spend preparing the more detailed material for the session itself (or playing).

Also, just because you are placing your campaign in an existing setting doesn't mean that there isn't room for your own creativity:

• Factions: The campaign setting might describe the major factions with world-wide influence, but that doesn't mean that there aren't any local factions which aren't powerful enough to influence world politics but are very important for what happens in a city or smaller region. So you can make up your own tribes, cults, warlords, guilds, secret societies or other small but interesting groups of people.
• Locations: Most campaign settings only describe a few major locations and leave large parts of the world only vaguely described. That leaves you a lot of room for coming up with interesting locations to populate these areas with.
• Deities: This might vary from setting to setting, but the cosmology of some of them allows lesser deities to coexist with the major pantheon of gods. They might not be as powerful and might not have as many followers, but they can still be important enough for a plot or two.
• NPCs: Most campaign settings only describe a few celebrity characters. Sometimes they even provide detailed character sheets for them. But be honest: It isn't very likely that your party of adventurers will only interact with these people. There are millions of people in the world for your players to meet, and it is your job to come up with unique personalities, backgrounds and (if necessary) character stats for them.

But remember that your players said that they want to play a specific campaign world and they expect you to deliver. Make sure your own creations do not completely overshadow the material from the setting. When you promise them Greyhawk and then give them nothing from the setting and only feed them your own stuff instead, they will feel cheated. So make sure you find a healthy mix of the official material and your own material.