The Tense Policy is a policy that deals with the use of tense of this site.
Introductory paragraph/characteristics section
If the subject of an article is in an object or concept in perpetuity, or a character that is currently alive, the introductory paragraph should use present tense where appropriate. A character was born, but is stubborn. He was Decepticon Leader, but is now an Autobot.
If the subject of an article is an object or concept that is no longer current, or a character that is dead, the introductory paragraph should use past tense. A character was born, he lived, and he died. He was Autobot leader and he was heroic.
The part of the article that deals with the subject's past should be written in past-tense. Was, not is. The only exceptions are qualifiers that suggest potential future storylines (or lack thereof), such as, "His ultimate fate is unknown."