Crown Princess Victoria represented the Swedish Royal Family at Nelson Mandela’s memorial service in Johannesburg today. She wore a simple black straw picture hat with band around the crown.
In sorting through pictures from this event, I do not believe any of the other royals in attendance wore a hat.
Photo from Odd Anderson/AFP via The Swedish Royal Court
Royal Hats 
Crown Princess Victoria does not wear hats as much as some of the other royals, so I was glad to see she wore one on this occasion. It is simple and understated and perfect for the occasion where it was worn. However, something seems slightly off about this hat for me. It may possibly be her severe hairstyle which is making me feel strange about this hat. The hairstyle combined with the rounded crown reminds me of an egg. I think the hat would have looked much better combined with a “softer” hairstyle.