due to the fact that; because of ~
States a reason or cause using a factual situation, often with a sense of being moved or affected.
とあって is a formal, written-style expression that introduces a reason or cause. It often carries a nuance of 'given the situation, it's natural that...' and is used when the speaker is explaining why something happened or why people behaved in a certain way. It is common in news reports, essays, and literary works. You will rarely hear it in casual conversation; instead, you might use ので or から.
Unlike ので, which simply states a cause, とあって adds a slightly explanatory or judgmental tone, as if the speaker is assessing the situation. It can also sound a bit dramatic, emphasizing the scale or importance of the reason. For example, if a famous actor appears, the excitement is justified by the situation.
Because it is N1, it is safe to use in written contexts, but be cautious in everyday speech—it may sound stiff. Also, note that とあって is not used with volitional expressions or commands; it only states facts.