A dinner commemorated the reopening of the wing and its revamped collection of work from Africa, the ancient Americas and Oceania.

The late scion of an American dynasty died under bizarre circumstances 64 years ago. Now, a wing of the Metropolitan Museum named for him is reopening and putting him back in the spotlight.

Almost 2,000 objects from three disparate geographic areas are back on view at The Met in a light-filled wing overlooking ...