The context of a "container" contains the container. Of course this question can be asked until infinity which implies no answer at all. Only an absolutely ultimate context ("container") can contain all that is relatively contained by something else. Conceivably this can be know as God....the only conceivable entity/reality that is both absolute an ultimate. There is a related question: what is the meaning of being contained by or within? Interesting :)
It depends with which container you are talking about, because philosophically speaking the container of life is contained in the earth. In addition, it may also mean a container that is being contained in a ship while in transit.