Victoria 3's major free update changes how wars work, but your old saves won't make the jump
Victoria 3's Update 1.15 is out, bringing a reworked war support system, a new resource and changes to the journal in Paradox Interactive's grand strategy game. There is an important catch for anyone in the middle of a campaign: the developer says old saves are incompatible with the new version because of map and mechanical changes.
The free update arrived on November 5 alongside State and Revolution, a separate paid immersion pack focused on Russia. You do not need to buy the pack to receive the base-game changes. Players who want to finish an existing campaign should back up their save and use an earlier version rather than assume it will load in 1.15.
Paradox also warns that mods need to be updated for the new release. Its release notes recommend disabling mods and testing a fresh save when investigating problems.

Image: Paradox Interactive
Wars can now shift before they end
The free update changes war support to a measure from 0% to 100% that can rise or fall during a conflict. Battles, occupation, war-goal progress, devastation, economic decline and the length of the war are among the factors that can influence it.
Low support has consequences: according to the developer's release notes, it can radicalize the population, weaken military forces and increase liberty desire among subject countries involved in the war. Countries no longer automatically capitulate simply because support reaches zero.
War goals can also be enforced during a war when the objective is controlled and enforcement progress is completed. The opposing side can receive a corresponding goal to recover what it lost, creating the possibility that territory or subjects change hands more than once before a war ends. Some goals, including regime change, still require capitulation or a peace deal.

Image: Paradox Interactive
Copper and a more useful journal
Copper joins the game's goods and can be mined from the start. Paradox says its demand grows over time, particularly as electricity arrives. That gives players another resource to consider when planning industries and trade.
The journal has received a visual overhaul, with objectives pinned at the top and options to search and filter entries. Entries also show their activation conditions, what advances them and how they ended. The update includes five new achievements and a long list of AI and stability fixes.
State and Revolution is sold separately. Its additions include Russia-focused historical characters, events and journal content, while the update described above applies to owners of the base game. The publisher's announcement has more information on the paid pack.
If you plan to preserve a campaign, back up its saves before switching versions. Paradox says earlier branches are available for continuing older games, and notes that even saves from the 1.14 open beta are incompatible with 1.15. Check the developer's instructions and your installed mods before updating a campaign you want to keep.