Circumstance is used directly for:
For these cases, the preposition helps situate the background context in which the main event takes place. The background context is often realized as a subordinate clause preceding the main clause. It may also be realized as an adjective complement:
Relatedly, we use Circumstance to analyze involved in:
The object of the preposition is a noun denoting a containing event; it thus may help establish the place, time, and/or reason for the governing scene, but is not specifically providing any one of these, despite the locative preposition. These can be questioned (at least in some contexts) with Where? or When?. #013 entails #014:
which may be responsive to the questions Where are you? and What are you doing?.1 Journey-type objects are treated similarly:
These simultaneously express a Time and some element of causality similar to Purpose. But the PP is not exactly answering a Why? or When? question. Instead, the sentence most naturally answers a question like On what occasion was X done? or Under what circumstances did X happen?.