Anno Curruo

Origins
Where the demarcation device Anno Curruo (AC) began is as of yet unknown, however, it is quite obviously a means for tracking the years and works by counting the years back to an unknown human centered event 300 years ago. Where King Hel Ubrokin conquered 911 years ago, it would be counted as -611 AC. A fairly simple calendric system.

Problems
Obviously the AC counting system does not take into account any other races or historic events outside of humanity's reckoning. Further, the numbers tend to become meaningless if one goes back too far. For example "-47192 AC" could better be rendered as "47,492 years ago", however, the humans of Ociana are steeped in tradition, and would loath to give up their dating system.