Aurel Mertz, a Black comedian, host, podcaster, and actor, is certain:

Welcome to Wilhelmsplatz
From past times to the present. From faraway places to here: Colonialism is not a topic of the past and also not one that merely concerns the distant former colonies. Colonialism continues to impact today’s life and is, among other things, responsible for the racism that is still present in our society as well as in many other places.
[A small hint: If you are interested in definitions of terms like “colonialism”, “racism” or similar, please have a look at the pages of IDA e.V., their glossary can be found here. The definitions are in German though.]
Look at the monument on this square: above you, as in many places in Germany, sits a king -in this case, King William IV of the United Kingdom of Great Britain and Ireland and, in personal union, King of Hanover from 1830-1837.
What does he have to do with colonialism and why does he appear at the beginning of this tour?
William IV had an established racist worldview even before he became king. In a speech to Parliament in 1799, he consequently advocated for the continuation of slavery, among other things (more information: here (English)).
Should people like him be honored with such a monument?
When colonial history is addressed, the focus is usually on the “great colonial powers” such as Great Britain, France, and Spain. The colonial empires of Russia, Japan, the USA, the Netherlands, Belgium, and Italy are rarely discussed. In particular, it is noteworthy that even in our country the colonial history of the German Empire is hardly taken into account. But the size of the German colonial empire was about 2.9 million km² in 1914- more than eight times the area of the Federal Republic of Germany today.
Do you know which territories were colonized by the German Empire?
A detailed chronology can be found on the pages of the Federal Agency for Civic Education (Bundeszentrale für politische Bildung) here (German).
If you like, you can also watch a short video as an introduction to German colonialism. We recommend the explanatory video (German) of the TAZ with the social scientist Imeh Ituen.