Elder Kings is a total conversion mod for the grand strategy game Crusader Kings II. Crusader Kings II is a dynasty simulator set in medieval Europe depicting characters and how they relate to other characters and the various territories they rule, with intersections between character traits, cultures, religions, and holdings. Players take control of a feudal ruler and their dynasty, and play it from the game's start date to the game's end date. Elder Kings changes the setting to Nirn from the start of the Interregnum to the Tiber Wars (including Tiber Septim as a 'late game crisis'), replacing the map and the various traits, cultures, and religions with Elder Scrolls equivalents.
The mod began development in 2011, was released in August 2012, and has continued development until the present day, though much of its development team has diverted to Elder Kings II. It features the continent of Tamriel, as well as Akavir, Atmora, Yokuda and Pyandonea. Like in Crusader Kings II, these lands are divided into hierarchical tiers of titles which can be held by characters, many of whom are playable. Counties and characters adhere to religions and cultures, and characters also have various traits which alter their attributes and represent various personalities and reputations. Just as in its base game, these characters can engage through diplomacy and war, and events with varying effects on characters and territory can occur throughout playthroughs.