Bannerlord Coop

Experience the Mount & Blade II: Bannerlord campaign with your friends.

Build armies, manage kingdoms, fight battles, trade, raid settlements, and conquer Calradia together in a shared multiplayer campaign.

Steam Workshop  •  Discord  •  Reddit  •  Support the project

About the Mod

Bannerlord Coop transforms Bannerlord's single-player campaign into a cooperative multiplayer experience.

Players share the same persistent campaign world while controlling their own characters, parties, clans, troops, and resources. Travel across the campaign map together, interact with settlements and NPC parties, or fight alongside — and against — other players.

The mod is currently optimized for campaigns with up to 8 players. Larger groups may work, but could experience reduced performance and stability.

Installation

Subscribe on the Steam Workshop, then enable the Coop module in the Bannerlord launcher.

Join our Discord for installation help, announcements, bug reports, playtests, and community discussion.

Hosting

For the best performance and stability, we strongly recommend hosting campaigns through the included dedicated server. The hosting instructions can be found in our Discord through this link.

Steam hosting does not require traditional port forwarding in most cases. Manual network hosting options are also available.

Dedicated-server operators can block Steam64 identities with a server-side ban list.

Server setup walkthrough: https://www.youtube.com/watch?v=laZM967Eals

Roadmap

https://bannerlordcoop.com/#roadmap

Multiplayer Battles

Players can participate in field battles and sieges as allies or opponents. AI parties may also join active battles under supported campaign conditions.

Players who retreat or disconnect are handled by the campaign and battle synchronization systems, allowing the shared game to continue without ending the entire session.

Compatibility

For the most reliable experience:

• Use the supported Bannerlord game version (currently v1.4.8)
• Disable all other mods
• Do not enable the War Sails DLC
• Ensure every player is using the same mod version

Compatibility with other mods is not guaranteed.

Feedback and Bug Reports

Please share your honest experience with the mod — good or bad. Detailed feedback and reproducible bug reports are extremely valuable and help us improve stability, performance, and gameplay.

Report bugs in our Discord or via GitHub issues, and please include:

• What happened
• What you expected to happen
• Steps that reproduce the problem
• Relevant screenshots, videos, or log files
• The number of connected players

Support Bannerlord Coop

Bannerlord Coop is developed by a volunteer team and will always be available for free.

Support helps cover development tools, hosting infrastructure, dedicated servers, distribution costs, and other project expenses. Choose whichever platform works best for you:

• Patreon — Become a monthly supporter
• Buy Me a Coffee — Send a one-time contribution
• PayPal — Donate directly
• Afdian — Support us from China
• Boosty — Additional international support option

Financial support is completely optional. Playing the mod, reporting bugs, creating content, and sharing Bannerlord Coop also help the project tremendously.

Contributing

Get started here! Also join our Discord for direct questions and collaboration.

We do not accept tests or implementations that no human contributor takes ownership of, because they add too much technical debt. AI tools may write code and tests, but a human contributor must own every change: direct its design, review and test it, answer review feedback, and be able to explain and maintain it. PRs that nobody owns this way may be closed.

Debug builds of the in-game server always try to load a campaign save named MP when the server starts: a plain /server launch loads nothing else, and a /coopsave <name> launch attempts MP before the named save. A missing MP save is skipped with Failed to load save with name MP in the server log, so create a game and save it as MP before hosting from a Debug build; the Environment Setup Guide wiki page covers this under Windows Setup (create a new game and save it as MP). Release builds skip MP and load only the save picked in the host screen or passed with /coopsave.

By submitting a contribution to BannerlordCoop, you agree that your contribution may be used, modified, distributed, sublicensed, and relicensed by the BannerlordCoop project maintainers as part of the BannerlordCoop project.

You also confirm that you have the right to submit the contribution and that it does not knowingly include code copied from another project without permission.

FAQ

Please read through the #faq channel in our discord server.

License

Bannerlord Coop is source-available, not open source. The code may be viewed and contributed to, but it may not be copied, redistributed, relicensed, or used in another project without written permission from the maintainers. See LICENSE and NOTICE.md for the full terms.

Acknowledgments

• Salminar for NoHarmony.