Thank you, Iceflower.
The premises behind the exhibition is partly the emancipation of slaves in the Danish West Indies, which were initiated (and actually without political OK back in Copenhagen) by the governor Peter von Scholten. He on the other hand was very much influenced by his black mistress and former slave... Who may actually by honored to the same degree. I can't even remember her name off hand, but that's how history goes.
The other occasion for the exhibition is that the islands of Skt Thomas, Skt. Croix and Skt Jan were sold to USA in 1917, where they are now knows as the Virgin Islands. - The locals were not heard, let alone asked whether they wanted to be Americans.
By that sale the last Danish tropical colony was left.
The islands were never a real goldmine for Denmark, except as a hub for slave transports in the 1700's. Most of the plantations were owned by foreigners or foreign companies.
By the early 1800's slavery had long since been outlawed in Denmark, but it was still legal in some colonies, but no one really wanted to know about it and fewer wanted to talk about it. It was a classical question of out of sight, out of mind. So when the governor Peter von Scholten decided to abolish slavery (as the first colony in the Caribbeans IIRC) the public and politicians back in Denmark took that ad notam. There was neither the political will nor public support in opposing that, even though the governor was actually performing a de facto local political coup.
That meant that the tax revenue from the islands fell even more and by 1917, the islands were basically a forgotten colonial backwater. So when USA came up with an offer "Denmark couldn't refuse" it was accepted.
DK, not being involved in WWI, had no interest in antagonizing USA and having the trade disrupted and USA might get the idea of "occupying the islands for protection", because USA at the time pursued a policy of exerting its influence directly and indirectly as much as possible in the Americas, as a direct consequence of the Monroe Doctrine.
So in 1917 Dannebrog was lowered and Stars and Stripes went to the top instead. - The anniversary was attended by Danish politicians but not the DRF. Because no one in DK cares and there is the question of an official apology for the period of slavery (followed by a suit of compensation) for which there is no political will to offer in DK.
So it has all been boiled down to an exhibition.
Always thankful for the great history lessons 
