Canon 1000 d wont turn on

Did you try to recharge the battery? Check if the battery contacts are still clean and shiny? Is the lens still connected as it should be?
These things I should check as a first reaction.
Is the battery still ok, after you charged it? batteries, sometimes just stop working. There is not such thing as a lifetime for a battery that is at least xx months or years. Some batteries die within one year, some survive 10 years. When the camera does not start, place the battery on the list as number one of the suspects.